99 results on '"Fu-Lin, Zhang"'
Search Results
2. Unambiguous State Discrimination with Intrinsic Coherence.
- Author
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Jin-Hua Zhang, Fu-Lin Zhang, Zhi-Xi Wang, Hui Yang, and Shao-Ming Fei
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- 2022
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3. Networks with pixels embedding: a method to improve noise resistance in images classification.
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Chi-Chun Zhou, Hai-Long Tu, Yi Liu, and Fu-Lin Zhang
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- 2020
4. Unambiguous State Discrimination with Intrinsic Coherence
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Jin-Hua Zhang, Fu-Lin Zhang, Zhi-Xi Wang, Hui Yang, and Shao-Ming Fei
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mixed state discrimination ,coherence ,quantum filtering ,Science ,Astrophysics ,QB460-466 ,Physics ,QC1-999 - Abstract
We investigate the discrimination of pure-mixed (quantum filtering) and mixed-mixed states and compare their optimal success probability with the one for discriminating other pairs of pure states superposed by the vectors included in the mixed states. We prove that under the equal-fidelity condition, the pure-pure state discrimination scheme is superior to the pure-mixed (mixed-mixed) one. With respect to quantum filtering, the coherence exists only in one pure state and is detrimental to the state discrimination for lower dimensional systems; while it is the opposite for the mixed-mixed case with symmetrically distributed coherence. Making an extension to infinite-dimensional systems, we find that the coherence which is detrimental to state discrimination may become helpful and vice versa.
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- 2021
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5. Unsteady state precipitation of M23C6 carbides during thermal cycling in reduced activation steel manufactured by laser melting deposition
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Ji-xin Hou, Fu-lin Zhang, Zhi-xin Xia, Yun-he Yu, Hai-ying Fu, Shu-hai Huang, Qian An, and Chi Zhang
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Mechanics of Materials ,Materials Chemistry ,Metals and Alloys - Published
- 2022
6. miR-206 enhances nasopharyngeal carcinoma radiosensitivity by targeting IGF1
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Tian Wang, Xin-Min Dong, Fu-Lin Zhang, and Ji-Ren Zhang
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Nasopharyngeal carcinoma ,Radioresistance ,miR-206 ,IGF1 ,PI3K/AKT pathway ,Medicine (General) ,R5-920 - Abstract
Radioresistance remains a major problem in nasopharyngeal carcinoma (NPC) treatment. However, the underlying molecular mechanisms of NPC radioresistance remain poorly understood. The present study aimed to investigate the potential role and mechanism of miR-206 in NPC radioresistance. We observed that miR-206 was down-regulated in radioresistant NPC cells. Furthermore, restoration of miR-206 in CNE2-IR cells suppressed enhanced radiosensitivity of NPC cells. In contrast, inhibition of miR-206 in CNE2 cells reduced the radiosensitivity. We also found that miR-206 directly targeted IGF1 and inhibited the PI3K/AKT pathway. Our data demonstrate that miR-206 sensitizes NPC cell to irradiation by targeting IGF1, highlighting the therapeutic potential of miR-206 in NPC radiosensitization.
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- 2017
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7. Thermodynamically consistent master equation based on subsystem eigenstates
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Si-Ying Wang, Qinghong Yang, and Fu-Lin Zhang
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Quantum Physics ,FOS: Physical sciences ,Quantum Physics (quant-ph) - Abstract
Master equations under appropriate assumptions are efficient tools for the study of open quantum systems. For many-body systems, subsystems of which locally couple to thermal baths and weakly interact with each other, the local approach provides a more convenient description than the global approach. However, these local master equations are believed to generate inconsistencies with the laws of thermodynamics when intersubsystem interactions exist. Here we develop an alternative local master equation by virtue of similar approximations used in deriving the traditional Gorini-Kossakowski-Lindblad-Sudarshan master equation. In particular, we stick to using eigenstates of each subsystem to construct quantum jump operators, and the secular approximation is also employed to modify the intersubsystem interactions. Our results show that violations of thermodynamic laws will be avoided after correcting intersubsystem interactions. Finally, We study a two-qubit heat transfer model and this further shows the validity of our modified master equation., 10 pages
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- 2022
8. Aircraft wake recognition based on deep learning
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fu lin zhang, Jianbing Li, and Hang Gao
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- 2022
9. Preparation of quantum correlations assisted by a steering Maxwell demon
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Gang-Gang He and Fu-Lin Zhang
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Quantum Physics ,FOS: Physical sciences ,Quantum Physics (quant-ph) - Abstract
A Maxwell demon can reduce the entropy of a quantum system by performing measurements on its environment. The nonsignaling theorem prevents the demon from affecting the average state of the system. We study the preparations of quantum correlations from a system qubit and an auxiliary qubit, assisted by a demon who obtains information of the system qubit from measurements on its environment. The demon can affect the postmeasured states of system by choosing different measurements, which establishes the relationships between quantum steering and other correlations in the thermodynamic framework. We present the optimal protocols for creating mutual information, entanglement, and Bell-nonlocality. These maximal correlations are found to relate exactly to the steerable boundary of the system-environment state with maximally mixed marginals. We also present upper bounds of the prepared correlations by utilizing classical environment-system correlation, which can be regarded as steering-type inequalities bounding the correlations created with the aid of classical demons., 8 pages, 3 figures. Published version
- Published
- 2022
10. Quantum information masking of an arbitrary unknown state can be realized in the multipartite lower-dimensional systems
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Wei-Min Shang, Xing-Yan Fan, Fu-Lin Zhang, and Jing-Ling Chen
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Condensed Matter Physics ,Mathematical Physics ,Atomic and Molecular Physics, and Optics - Abstract
Quantum information masking is a protocol that hides the original quantum information from subsystems and spreads it over quantum correlation, which is available to multipartite except bipartite systems. In this work, we explicitly study the quantum information masking in multipartite scenario and prove that there exists an universal quantum masker can mask the information encoding in the unknown states into a multipartite system with lower-dimensional local systems, namely, all the k-level quantum states can be masked into a m-qudit systems (m ≥ 4) whose local dimension d ≤ k . In order to observe the masking process intuitively, explicitly controlled operations are provided. Our scheme well demonstrates the abundance of quantum correlation between multipartite quantum system and has potential application in the security of quantum information processing.
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- 2023
11. Masking quantum information in the Kitaev Abelian anyons
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Yao Shen, Fu-Lin Zhang, Yu-Zhu Chen, and Chi-Chun Zhou
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Statistics and Probability ,Statistical and Nonlinear Physics - Published
- 2023
12. Most robust and fragile two-qubit entangled states under depolarizing channels.
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Chao-Qian Pang, Fu-Lin Zhang, Yue Jiang, Mai-Lin Liang, and Jing-Ling Chen
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- 2013
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13. Two‐step locating method for aircraft wake vortices based on Gabor filter and velocity range distribution
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Chun Shen, K. K. Hon, Fu-lin Zhang, Jianbing Li, Pak Wai Chan, and Xuesong Wang
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Computer science ,Acoustics ,020206 networking & telecommunications ,02 engineering and technology ,Wake ,International airport ,Vortex ,Vehicle dynamics ,Aviation safety ,Noise ,Gabor filter ,Range (aeronautics) ,0202 electrical engineering, electronic engineering, information engineering ,Electrical and Electronic Engineering - Abstract
Aircraft wake is a pair of strong counter-rotating vortices generated behind a flying aircraft, which might be dangerous to the following aircrafts. The real-time and precise locating of aircraft wake vortex-core positions is essential in the aviation safety field, especially in airport traffic management. This study proposes a two-step vortex-core locating method which uses the Gabor filter to make a preliminary locating and the velocity range distribution to make a fine locating consequently. The combination of Gabor filter and Doppler velocity distribution can improve the method's adaptability to complex background wind field and mitigate the impact of noise. Numerical examples and field detection campaigns from Changsha Huanghua International Airport and Hong Kong International Airport have well verified the good performance of the method, in terms of both accuracy and real time.
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- 2020
14. Quantum cloning of steering
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Dian Zhu, Wei-Min Shang, Fu-Lin Zhang, and Jing-Ling Chen
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Quantum Physics ,General Physics and Astronomy ,FOS: Physical sciences ,Quantum Physics (quant-ph) - Abstract
Quantum steering in a global state allows an observer to remotely steer a subsystem into different ensembles by performing different local measurements on the other part. We show that, in general, this property cannot be perfectly cloned by any joint operation between a steered subsystem and a third system. Perfect cloning is viable if and only if the initial state is of zero discord. We also investigate the process of cloning the steered qubit of a Bell state using a universal cloning machine. Einstein-Podolsky-Rosen (EPR) steering, which is a type of quantum correlation existing in the states without a local-hidden-state model, is observed in the two copy subsystems. This contradicts the conclusion of no-cloning of quantum steering (EPR steering) [C. Y. Chiu et al., npj Quantum Inf. 2, 16020 (2016)] based on a mutual information criterion for EPR steering., Comment: Published by CPL as Editors' Suggestion; This work has been reported in Physics World (https://physicsworld.com/a/cloning-quantum-steering-is-a-no-go/)
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- 2022
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15. Hear $π$ from Quantum Galperin Billiards
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Yin Cai and Fu-Lin Zhang
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General Physics and Astronomy ,FOS: Physical sciences ,Chaotic Dynamics (nlin.CD) ,Quantum Physics (quant-ph) - Abstract
Galperin [Regul. Chaotic. Dyn. 8, 375 (2003)] introduced an interesting method to learn the digits of $π$ by counting the collisions of two billiard balls and a hard wall. This paper studies two quantum versions of the Galperin billiards. It is shown that the digits of $π$ can be observed in the phase shifts of the quantum models., 5 figures,4 pages
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- 2022
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16. Robust violation of a multipartite Bell inequality from the perspective of a single-system game
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Gang-Gang He, Xing-Yan Fan, and Fu-Lin Zhang
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Quantum Physics ,Nuclear and High Energy Physics ,General Physics and Astronomy ,FOS: Physical sciences ,Astronomy and Astrophysics ,Quantum Physics (quant-ph) ,Physics::History of Physics - Abstract
Recently, Fan \textit{et al.} [Mod. Phys. Lett. A 36, 2150223 (2021)], presented a generalized Clauser-Horne-Shimony-Holt (CHSH) inequality, to identify $N$-qubit Greenberger-Horne-Zeilinger (GHZ) states. They showed an interesting phenomenon that the maximal violation of the generalized CHSH inequality is robust under some specific noises. In this work, we map the inequality to the CHSH game, and consequently to the CHSH* game in a single-qubit system. This mapping provides an explanation for the robust violations in $N$-qubit systems. Namely, the robust violations, resulting from the degeneracy of the generalized CHSH operators correspond to the symmetry of the maximally entangled two-qubit states and the identity transformation in the single-qubit game. This explanation enables us to exactly demonstrate that the degeneracy is $2^{N-2}$., Comment: 9 pages, 2 figures
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- 2022
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17. Sequential state discrimination with quantum correlation.
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Jinhua Zhang, Fu-Lin Zhang, and Mai-Lin Liang
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- 2018
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18. Nonequilibrium quantum absorption refrigerator
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Jian-Ying Du and Fu-Lin Zhang
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nonequilibrium steady-state ,quantum absorption refrigerator ,quantum coherence ,master equation ,Science ,Physics ,QC1-999 - Abstract
We study a quantum absorption refrigerator, in which a target qubit is cooled by two machine qubits in a nonequilibrium steady-state. It is realized by a strong internal coupling in the two-qubit fridge and a vanishing tripartite interaction among the whole system. The coherence of a machine virtual qubit is investigated as quantumness of the fridge. A necessary condition for cooling shows that the quantum coherence is beneficial to the nonequilibrium fridge, while it is detrimental as far as the maximum coefficient of performance (COP) and the COP at maximum power are concerned. Here, the COP is defined only in terms of heat currents caused by the tripartite interaction, with the one maintaining the two-qubit nonequilibrium state being excluded. The later can be considered to have no direct involvement in extracting heat from the target, as it is not affected by the tripartite interaction.
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- 2018
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19. Study On Mechanical-Electric Domain Change Effect Of 2-2 Cement-Based Piezoelectric Composites With Optimized PZT Width-To-Thickness Ratio
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Wen-jie Cheng, Yi Li, Hai-wei Dong, Jiang-ying Chen, and Fu-lin Zhang
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Stress (mechanics) ,Materials science ,Volume fraction ,Coupling (piping) ,Dielectric ,Composite material ,Material properties ,Piezoelectricity ,Sensitivity (electronics) ,Critical point (mathematics) - Abstract
The mechanical- electric domain change effect of 2-2 cement-based piezoelectric composites with the optimal PZT width-to-thickness ratio were studied. The comprehensive performance of the material with the constant PZT volume fraction under different PZT width-to-thickness ratio was compared and the optimal ratio was selected. Based on this, MTS testing machine was used to carry out static compression experiments on 2-2 cement-based piezoelectric composites. The XRD changes of the samples were measured before and after the experiments. The law of the influence of mechanical-electric domain change effect on the properties of materials was acquired. The research results show that when the PZT width-to-thickness ratio is 0.125, the 2-2 cement-based piezoelectric composite has the highest sensitivity, and the electric-mechanical coupling factor, piezoelectric properties and dielectric properties are comprehensively optimal. When the loading reaches a certain value, the material will happen domain switching, and the amount of domain switching increases with the increase of stress. When the stress is near 35MPa, the domain switching reaches a critical point, and there is a “sudden jump” about the percentage of domain switching. When the stress is larger than 35MPa, the domain switching percentage is proportional to the maximum stress.
- Published
- 2021
20. Locality of three-qubit Greenberger-Horne-Zeilinger-symmetric states
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Dian Zhu, Gang-Gang He, and Fu-Lin Zhang
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Quantum Physics ,FOS: Physical sciences ,Quantum Physics (quant-ph) - Abstract
The hierarchy of nonlocality and entanglement in multipartite systems is one of the fundamental problems in quantum physics. We study this topic in three-qubit systems considering the entanglement classification of stochastic local operations and classical communication (SLOCC). The equivalence under SLOCC divides threequbit states into separable, biseparable, W, and Greenberger-Horne-Zeilinger (GHZ) classes. The W and GHZ are two subclasses of genuine tripartite entanglement.We adopt the family of GHZ-symmetric states as a research subject, which share the symmetries of the GHZ state and have a complete characterization of SLOCC classes. In the biseparable region (with bipartite entanglement), there exist GHZ-symmetric states that are found to be fully local. In addition, there are bilocal states in both theW and GHZ classes. That is, neither of the subclasses of genuine tripartite entanglement can ensure genuinely tripartite nonlocality., 4 figures, 7 pages
- Published
- 2021
21. Perfect teleportation with a partially entangled quantum channel
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Xiang Chen, Yao Shen, and Fu-Lin Zhang
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Quantum Physics ,FOS: Physical sciences ,Quantum Physics (quant-ph) - Abstract
Quantum teleportation provides a way to transfer unknown quantum states from one system to another via an entangled state as a quantum channel without physical transmission of the object itself. The entangled channel, measurement performed by the sender (Alice), and classical information sent to the receiver (Bob) are three key ingredients in the procedure, which need to cooperate with each other. To study the relationship among the three parts, we propose a scheme for perfect teleportation of a qubit through a high-dimensional quantum channel in a pure state with two equal largest Schmidt coefficients. The scheme requires less entanglement of Alice's measurement but more classical bits than the original scheme via a Bell state. The two quantities increase with the entanglement of the quantum channel when its dimension is fixed and thereby can be regard as Alice's necessary capabilities to use the quantum channel. And the two capabilities appear complementary to each other., Comment: We added two references studying perfect teleportation via partially bipartite states
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- 2021
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22. Probabilistic resumable quantum teleportation in high dimensions
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Jin-Hua Zhang, Fu-Lin Zhang, and Xiang Chen
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Quantum Physics ,Computer science ,Probabilistic logic ,Measure (physics) ,General Physics and Astronomy ,FOS: Physical sciences ,Quantum channel ,Teleportation ,Computer Science::Emerging Technologies ,Quantum state ,Quantum information ,Quantum Physics (quant-ph) ,Quantum ,Algorithm ,Quantum teleportation - Abstract
Teleportation is a quantum information processes without classical counterparts, in which the sender can disembodied transfer unknown quantum states to the receiver. In probabilistic teleportation through a partial entangled quantum channel, the transmission is exact (with fidelity 1), but may fail in a probability and the initial state is destroyed simultaneously. We propose a scheme for nondestructive probabilistic teleportation of high-dimensional quantum states. With the aid of an ancilla in the hands of the sender, the initial quantum information can be recovered when teleportation fails. The ancilla acts as a quantum apparatus to measure the sender's subsystem. Erasing the information recorded in it can resume the initial state., Comment: 5 pages, 1 figure
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- 2021
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23. Discriminating bipartite mixed states by local operations
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Shao-Ming Fei, Jin-Hua Zhang, Le-Min Lai, Fu-Lin Zhang, and Zhi-Xi Wang
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Scheme (programming language) ,Physics ,Quantum Physics ,LOCC ,Mixed states ,FOS: Physical sciences ,Quantum entanglement ,State (functional analysis) ,Topology ,01 natural sciences ,010305 fluids & plasmas ,Broadcasting (networking) ,0103 physical sciences ,Bipartite graph ,Quantum Physics (quant-ph) ,010306 general physics ,computer ,Protocol (object-oriented programming) ,Computer Science::Databases ,computer.programming_language - Abstract
Unambiguous state discrimination of two mixed bipartite states via local operations and classical communications (LOCC) is studied and compared with the result of a scheme realized via global measurement. We show that the success probability of a global scheme for mixed-state discrimination can be achieved perfectly by the local scheme. In addition, we simulate this discrimination via a pair of pure entangled bipartite states. This simulation is perfect for local rather than global schemes due to the existence of entanglement and global coherence in the pure states. We also prove that LOCC protocol and the sequential state discrimination (SSD) can be interpreted in a unified view. We then hybridize the LOCC protocol with three protocols (SSD, reproducing, and broadcasting) relying on classical communications. Such hybridizations extend the gaps between the optimal success probability of global and local schemes, which can be eliminated only for the SSD rather than the other two protocols.
- Published
- 2020
24. Dynamical Algebras in the 1+1 Dirac Oscillator and the Jaynes-Cummings Model
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Fu-Lin Zhang and Wen-Ya Song
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Physics ,Quantum Physics ,Jaynes–Cummings model ,Algebraic structure ,Computer Science::Information Retrieval ,General Physics and Astronomy ,Cartan subalgebra ,FOS: Physical sciences ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Noncommutative geometry ,Conserved quantity ,Mathematics::Quantum Algebra ,0103 physical sciences ,Spin symmetry ,010306 general physics ,0210 nano-technology ,Quantum Physics (quant-ph) ,Eigenvalues and eigenvectors ,Dirac oscillator ,Mathematical physics - Abstract
We study the algebraic structure of the one-dimensional Dirac oscillator by extending the concept of spin symmetry to a noncommutative case. An SO(4) algebra is found connecting the eigenstates of the Dirac oscillator, in which the two elements of Cartan subalgebra are conserved quantities. Similar results are obtained in the Jaynes–Cummings model.
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- 2020
25. Intermediate symmetric construction of transformation between anyon and Gentile statistics
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Fu-Lin Zhang and Yao Shen
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Physics ,Theoretical physics ,Quantum Physics ,Transformation (function) ,Physics and Astronomy (miscellaneous) ,Anyon ,FOS: Physical sciences ,Quantum Physics (quant-ph) - Abstract
Gentile statistics describes fractional statistical systems in the occupation number representation. Anyon statistics researches those systems in the winding number representation. Both of them are intermediate statistics between Bose–Einstein and Fermi–Dirac statistics. The second quantization of Gentile statistics shows a lot of advantages. According to the symmetry requirement of the wave function and the property of braiding, we give the general construction of transformation between anyon and Gentile statistics. In other words, we introduce the second quantization form of anyons in an easier way. This construction is a correspondence between two fractional statistics and gives a new description of anyon. Basic relations of second quantization operators, the coherent state and Berry phase are also discussed.
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- 2020
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26. Experimental Study on Rockfall Impact Force Applied to Frame Shed Tunnels
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Yuan Wang, Xiao-jun Zhou, Fu-jun Luo, and Fu-lin Zhang
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geography ,geography.geographical_feature_category ,business.industry ,Frame (networking) ,0211 other engineering and technologies ,Improved method ,02 engineering and technology ,Structural engineering ,Rockfall ,021105 building & construction ,Cushion ,Impact energy ,Model test ,Impact ,business ,Roof ,Geology ,021101 geological & geomatics engineering - Abstract
A model experiment is performed to test the rockfall impact force applied to frame shed tunnels under the protection of different types of cushions embedded on tunnel roof slabs. The changing rule of impact force induced by rockfall is analyzed according to different impact energies and types of cushions embedded on shed tunnels. An enlargement coefficient reflecting the relationship between average impact force and maximum impact force is presented using experimental data and theoretical analysis. The improved method for calculating rockfall impact force can consider the many factors that affect this phenomenon. For a particular rockfall impact energy, the rockfall impact force with different types of cushion properties is affected by the cushion property function f~(h, E, μ, γ). A large f value equates to the minimal discreteness of the expansion coefficient of rockfall impact force under different types of cushion, and vice versa.
- Published
- 2018
27. miR-206 enhances nasopharyngeal carcinoma radiosensitivity by targeting IGF1
- Author
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Xinmin Dong, Tian Wang, Ji-Ren Zhang, and Fu-Lin Zhang
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0301 basic medicine ,Oncology ,medicine.medical_specialty ,Cell ,Radiation Tolerance ,Phosphatidylinositol 3-Kinases ,03 medical and health sciences ,0302 clinical medicine ,Cell Line, Tumor ,Nasopharynx ,Radioresistance ,Internal medicine ,Nasopharyngeal carcinoma ,otorhinolaryngologic diseases ,medicine ,Humans ,Radiosensitivity ,Insulin-Like Growth Factor I ,PI3K/AKT/mTOR pathway ,lcsh:R5-920 ,Binding Sites ,Base Sequence ,business.industry ,miR-206 ,IGF1 ,Antagomirs ,General Medicine ,medicine.disease ,PI3K/AKT pathway ,Gene Expression Regulation, Neoplastic ,MicroRNAs ,stomatognathic diseases ,030104 developmental biology ,medicine.anatomical_structure ,Gamma Rays ,030220 oncology & carcinogenesis ,Cancer research ,lcsh:Medicine (General) ,business ,Proto-Oncogene Proteins c-akt ,Signal Transduction - Abstract
Radioresistance remains a major problem in nasopharyngeal carcinoma (NPC) treatment. However, the underlying molecular mechanisms of NPC radioresistance remain poorly understood. The present study aimed to investigate the potential role and mechanism of miR-206 in NPC radioresistance. We observed that miR-206 was down-regulated in radioresistant NPC cells. Furthermore, restoration of miR-206 in CNE2-IR cells suppressed enhanced radiosensitivity of NPC cells. In contrast, inhibition of miR-206 in CNE2 cells reduced the radiosensitivity. We also found that miR-206 directly targeted IGF1 and inhibited the PI3K/AKT pathway. Our data demonstrate that miR-206 sensitizes NPC cell to irradiation by targeting IGF1, highlighting the therapeutic potential of miR-206 in NPC radiosensitization.
- Published
- 2017
28. Qubit masking in multipartite qubit system
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Fu-Lin Zhang, Hui-Xian Meng, Jie Zhou, Wei-Min Shang, and Jing-Ling Chen
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Physics ,Masking (art) ,Nuclear and High Energy Physics ,Quantum correlation ,Astrophysics::Instrumentation and Methods for Astrophysics ,TheoryofComputation_GENERAL ,General Physics and Astronomy ,Astronomy and Astrophysics ,Data_CODINGANDINFORMATIONTHEORY ,Quantum Physics ,Quantum entanglement ,01 natural sciences ,010305 fluids & plasmas ,Set (abstract data type) ,Multipartite ,Computer Science::Emerging Technologies ,Computer Science::Sound ,Qubit ,Quantum mechanics ,0103 physical sciences ,Bipartite graph ,Hardware_ARITHMETICANDLOGICSTRUCTURES ,010306 general physics - Abstract
The no-masking theories show that it is impossible to mask the set of all qubit states into the quantum correlation of bipartite qubit system or tripartite qubit system. In this paper, we give a new proof of the no-masking situation of the tripartite qubit system. Recent work has shown that there exists a universal masker which can mask an arbitrary set of qubit states in four-qubit systems perfectly by means of the maximum entangled states. Here we show that there exist more than one masking scheme even for the same multipartite qubit system. Basing on the maximum entangled states we give the deterministic masking scenario for N-qubit system. In practice, decoherence hinders us from obtaining the maximum entangled states. From this viewpoint, the masking scenario based on non-maximum entangled states becomes more universal. Furthermore, we provide an approximate quantum masking scenario and investigate the relation between approximate masking and quantum entanglement.
- Published
- 2021
29. Local-hidden-state models for T-states using finite shared randomness
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Yuan-Yuan Zhang and Fu-Lin Zhang
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Physics ,Quantum Physics ,Werner state ,General Physics and Astronomy ,Boundary (topology) ,FOS: Physical sciences ,Quantum entanglement ,01 natural sciences ,010305 fluids & plasmas ,Separable space ,Separable state ,0103 physical sciences ,Statistical physics ,010306 general physics ,Anisotropy ,Quantum Physics (quant-ph) ,Quantum ,Randomness - Abstract
The study of local models using finite shared randomness originates from the consideration about the cost of classically simulating entanglement in composite quantum systems. We construct explicitly two families of local-hidden-state (LHS) models for T-states, by mapping the problem to the Werner state. The continuous decreasing of shared randomness along with entanglement, as the anisotropy increases, can be observed in the one from the most economical model for the Werner state. The construction of the one for separable states shows that the separable boundary of T-states can be generated from the one of the Werner state, and the cost is 2 classical bits., 6 pages, 4 figures
- Published
- 2019
30. The Analytic Eigenvalue Structure of the 1+1 Dirac Oscillator
- Author
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Bo-Xing Cao and Fu-Lin Zhang
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Physics ,Antiparticle ,Quantum Physics ,Riemann surface ,General Physics and Astronomy ,FOS: Physical sciences ,State (functional analysis) ,symbols.namesake ,Quantum mechanics ,Principal quantum number ,symbols ,Negative energy ,Hamiltonian (quantum mechanics) ,Quantum Physics (quant-ph) ,Complex plane ,Eigenvalues and eigenvectors - Abstract
We study the analytic structure for the eigenvalues of the one-dimensional Dirac oscillator, by analytically continuing its frequency on the complex plane. A twofold Riemann surface is found, connecting the two states of a pair of particle and antiparticle. One can, at least in principle, accomplish the transition from a positive energy state to its antiparticle state by moving the frequency continuously on the complex plane, without changing the Hamiltonian after transition. This result provides a visual explanation for the absence of a negative energy state with the quantum number n=0., Comment: 5.3 pages, 3 figures
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- 2019
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31. Synthesis, Characterization, Properties and DFT Calculations of 2-(Benzo[b]thiophen-2-yl)pyridine-based Iridium(III) Complexes with Different Ancillary Ligands
- Author
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Gao-Nan Li, Kai-Xiu Li, Hui Xie, Guang-Ying Chen, Zhi-Gang Niu, Fu-Lin Zhang, Yong-Pi Zeng, and Hao-Hua Chen
- Subjects
Models, Molecular ,Sociology and Political Science ,Absorption spectroscopy ,Pyridines ,Clinical Biochemistry ,chemistry.chemical_element ,Thiophenes ,Crystal structure ,Crystallography, X-Ray ,Iridium ,Ligands ,010402 general chemistry ,Photochemistry ,01 natural sciences ,Biochemistry ,chemistry.chemical_compound ,Pyridine ,Bathochromic shift ,Organometallic Compounds ,Molecule ,Spectroscopy ,Molecular Structure ,010405 organic chemistry ,Ligand ,0104 chemical sciences ,Clinical Psychology ,Crystallography ,chemistry ,Quantum Theory ,Law ,Social Sciences (miscellaneous) - Abstract
A series of new cyclometalated btp-based iridium(III) complexes with three different ancillary ligands, Ir(btp)2(bozp) (3a), Ir(btp)2(btzp) (3b) and Ir(btp)2(izp) (3c) (btp = 2-(benzo[b]thiophen-2-yl)pyridine, bozp =2-(benzo[d]oxazol-2-yl)phenol, btzp =2-(benzo[d]thiazol-2-yl)phenol, izp = 2-(2 H-indazol-2-yl)phenol), have been synthesized and fully characterized. The crystal structure of 3b has been determined by single crystal X-ray diffraction analysis. A comparative study has been carried out for complexes 3a - 3c by UV-vis absorption spectroscopy, photoluminescence spectroscopy, cyclic voltammetry and DFT calculations. This observation illustrates that the substitution of N or S in ancillary ligand can lead to a marked bathochromic shift of absorption and emission wavelengths. The spectroscopic characterisation of these complexes has been complemented by DFT and TD-DFT calculations, supporting the assignment of (3)MLCT/(3)LC to the lowest energy excited state.
- Published
- 2015
32. [Characteristics of Nitrogen and Phosphorus Emissions in the Gufu River Small Watershed of the Three Georges Reservoir Area]
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Ling-Ling, Hua, Wen-Chao, Li, Li-Mei, Zhai, Chao, Cui, Hong-Bin, Liu, Tian-Zhi, Ren, Fu-Lin, Zhang, and Qiu-Liang, Lei
- Abstract
To study the seasonal change characteristics and form composition of nitrogen and phosphorus output concentration and pollutant discharge load with rainfall characteristics at the outlet of Gufu river small watershed,the quality and quantity of water combined with natural rainfall events were monitored from January to December 2014.The results showed that the annual runoff volume of the Gufu river small watershed was 0.6×10
- Published
- 2018
33. [Characteristics of Nitrogen and Phosphorus Concentration Dynamics in Natural Ditches Under an Irrigation-Drainage Unit in the Jianghan Plain]
- Author
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Ling-Ling, Hua, Fu-Lin, Zhang, Li-Mei, Zhai, Hong-Bin, Liu, Xian-Peng, Fan, and Hong-Yuan, Wang
- Abstract
The paddy field in Jianghan Plain usually exists in the form of an irrigation-drainage unit, and the natural ditch is the main part of the unit. A continuous in situ monitoring of the natural ditch water level and water quality through the entire rice growing season in 2015 was conducted to investigate the dynamics of ditch water level and nitrogen and phosphorus concentration in the ditch. Another objective was to determine the effect of these factors. Results showed that during the entire rice growing season, the ditch water depth was maintained between 30 to 70 cm, and the water depth was higher during irrigation events than during rainfall events. Fertilization was the main factor affecting the nitrogen concentration in the ditch water. Two peaks of total nitrogen (TN) concentration appeared on June 18 and July 30 because of topdressing. In the early stage of rice growing, ammonia nitrogen (NH
- Published
- 2018
34. Zitterbewegung in Bogoliubov's System
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Jing-Ling Chen, Chunfeng Wu, Yan Li, Fu-Lin Zhang, Kwek Leong-Chuan, and Hong-Yi Su
- Subjects
Condensed Matter::Quantum Gases ,Physics ,Physics and Astronomy (miscellaneous) ,Condensed Matter::Other ,Dirac (software) ,Electron ,Expectation value ,Condensed Matter::Mesoscopic Systems and Quantum Hall Effect ,Superfluidity ,Position (vector) ,Condensed Matter::Superconductivity ,Quantum mechanics ,Quasiparticle ,Condensed Matter::Strongly Correlated Electrons ,Zitterbewegung ,Spin-½ - Abstract
We show that Bogoliubov's quasiparticle in superfluid 3He-B undergoes the Zitterbewegung, as a free relativistic Dirac's electron does. The expectation value of position, as well as spin, of the quasiparticle is obtained and compared with that of the Dirac's electron. In particular, the Zitterbewegung of Bogoliubov's quasiparticle has a frequency approximately 105 lower than that of an electron, rendering a more promising experimental observation.
- Published
- 2015
35. Sequential state discrimination with quantum correlation
- Author
-
Mai-Lin Liang, Jin-Hua Zhang, and Fu-Lin Zhang
- Subjects
Quantum Physics ,Observer (quantum physics) ,Quantum correlation ,Probabilistic logic ,FOS: Physical sciences ,Statistical and Nonlinear Physics ,Quantum entanglement ,State (functional analysis) ,01 natural sciences ,010305 fluids & plasmas ,Theoretical Computer Science ,Electronic, Optical and Magnetic Materials ,Modeling and Simulation ,0103 physical sciences ,Signal Processing ,Electrical and Electronic Engineering ,Special case ,010306 general physics ,Quantum Physics (quant-ph) ,Algorithm ,Quantum ,Mathematics ,Quantum computer - Abstract
The sequential unambiguous state discrimination (SSD) of two states prepared in arbitrary prior probabilities is studied, and compared with three strategies that allow classical communication. The deviation from equal probabilities contributes to the success in all the tasks considered. When one considers at least one of the parties succeeds, the protocol with probabilistic cloning is superior to others, which is not observed in the special case with equal prior probabilities. We also investigate the roles of quantum correlations in SSD, and show that the procedure requires discords but rejects entanglement. The left and right discords correspond to the part of information extracted by the first observer and the part left to his successor respectively. Their relative difference is extended by the imbalance of prior probabilities., Comment: 16pages, 6figs. We have corrected a mistake in Eq. (7a)
- Published
- 2017
- Full Text
- View/download PDF
36. Solving the Jaynes-Cummings Model with Shift Operators Constructed by Means of the Matrix-Diagonalizing Technique
- Author
-
Hong-Biao Zhang, Jie Zhou, Jing-Ling Chen, Hong-Yi Su, and Fu-Lin Zhang
- Subjects
Physics ,Quantum Physics ,Jaynes–Cummings model ,010308 nuclear & particles physics ,General Physics and Astronomy ,FOS: Physical sciences ,01 natural sciences ,Raising (linguistics) ,Quantum nonlocality ,Matrix (mathematics) ,Quantum mechanics ,0103 physical sciences ,010306 general physics ,Quantum Physics (quant-ph) ,Excitation - Abstract
The Jaynes-Cummings model is solved with the raising and lowering (shift) operators by using the matrix-diagonalizing technique. Bell nonlocality is also found present ubiquitously in the excitations states of the model., Comment: 5 pages
- Published
- 2017
- Full Text
- View/download PDF
37. Sensorless Control of PMSM Based on Improved Sliding Mode Observer Method
- Author
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Zhi Fu Wang and Fu Lin Zhang
- Subjects
Observer (quantum physics) ,Control theory ,Computer science ,Control engineering ,General Medicine ,Observer (special relativity) ,Sigmoid function ,State observer - Abstract
This paper introduces an improved sliding mode observer for sensorless control of PMSM. In order to reduce the chattering phenomenon of traditional sliding mode observer, replace the ideal switching function with sigmoid function and use two-stage low frequency filter. At last, the simulation was done to verify the measures.
- Published
- 2014
38. Speed of disentanglement in multiqubit systems under a depolarizing channel
- Author
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Yue Jiang, Fu-Lin Zhang, and Mai-Lin Liang
- Subjects
Physics ,Quantum Physics ,FOS: Physical sciences ,General Physics and Astronomy ,Concurrence ,Quantum entanglement ,Upper and lower bounds ,Superposition principle ,Computer Science::Emerging Technologies ,Greenberger–Horne–Zeilinger state ,Robustness (computer science) ,Quantum mechanics ,Qubit ,W state ,Quantum Physics (quant-ph) - Abstract
We investigate the speed of disentanglement in the multiqubit systems under the local depolarizing channel, in which each qubit is independently coupled to the environment. We focus on the bipartition entanglement between one qubit and the remaining qubits constituting the system, which is measured by the negativity. For the two-qubit system, the speed for the pure state completely depends on its entanglement. The upper and lower bounds of the speed for arbitrary two-qubit states, and the necessary conditions for a state achieving them, are obtained. For the three-qubit system, we study the speed for pure states, whose entanglement properties can be completely described by five local-unitary-transformation invariants. An analytical expression of the relation between the speed and the invariants is derived. The speed is enhanced by the the three-tangle which is the entanglement among the three qubits, but reduced by the the two-qubit correlations outside of the concurrence. The decay of the negativity can be restrained by the other two negativity with the coequal sense. The unbalance between two qubits can reduce speed of disentanglement of the remaining qubit in the system, even can retrieve the entanglement partially. For the k-qubit systems in an arbitrary superposition of GHZ state and W state, the speed depends almost entirely on the amount of the negativity when k increases to five or six. An alternative quantitative definition for the robustness of entanglement is presented based on the speed of disentanglement, with comparison to the widely studied robustness measured by the critical amount of noise parameter where the entanglement vanishes. In the limit of large number of particles, the alternative robustness of the GHZ-type states is inversely proportional to k, and the one of the W states approaches 1/\sqrt{k}., Comment: 14 pages, 5 figures. to appear in Annals of Physics
- Published
- 2013
39. Most robust and fragile two-qubit entangled states under deploarizing channels
- Author
-
Yue Jiang, Fu-Lin Zhang, Chao-Qian Pang, Mai-Lin Liang, and Jing-Ling Chen
- Subjects
Nuclear and High Energy Physics ,Generalization ,media_common.quotation_subject ,General Physics and Astronomy ,Statistical and Nonlinear Physics ,Concurrence ,Quantum entanglement ,Asymmetry ,Multipartite entanglement ,Theoretical Computer Science ,Computational Theory and Mathematics ,Robustness (computer science) ,Qubit ,Quantum mechanics ,Mathematical Physics ,Mathematics ,media_common ,Ansatz - Abstract
For a two-qubit system under local depolarizing channels, the most robust and most fragile states are derived for a given concurrence or negativity. For the one-sided channel, the pure states are proved to be the most robust ones, with the aid of the evolution equation for entanglement given by Konrad \emph{et al.} [Nat. Phys. 4, 99 (2008)]. Based on a generalization of the evolution equation for entanglement, we classify the ansatz states in our investigation by the amount of robustness, and consequently derive the most fragile states. For the two-sided channel, the pure states are the most robust for a fixed concurrence. Under the uniform channel, the most fragile states have the minimal negativity when the concurrence is given in the region $[1/2,1]$. For a given negativity, the most robust states are the ones with the maximal concurrence, and the most fragile ones are the pure states with minimum of concurrence. When the entanglement approaches zero, the most fragile states under general nonuniform channels tend to the ones in the uniform channel. Influences on robustness by entanglement, degree of mixture, and asymmetry between the two qubits are discussed through numerical calculations. It turns out that the concurrence and negativity are major factors for the robustness. When they are fixed, the impact of the mixedness becomes obvious. In the nonuniform channels, the most fragile states are closely correlated with the asymmetry, while the most robust ones with the degree of mixture.
- Published
- 2013
40. Intrinsic coherence in assisted sub-state discrimination
- Author
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Teng Wang and Fu-Lin Zhang
- Subjects
Quantum Physics ,010308 nuclear & particles physics ,Computer science ,Process (computing) ,Probabilistic teleportation ,General Physics and Astronomy ,FOS: Physical sciences ,Coherence (statistics) ,Quantum entanglement ,Quantum channel ,State (functional analysis) ,01 natural sciences ,Qubit ,0103 physical sciences ,Key (cryptography) ,Statistical physics ,010306 general physics ,Quantum Physics (quant-ph) - Abstract
We study intrinsic coherence in the tripartite process to unambiguously discriminate two nonorthogonal states of a qubit, entangled with another one, and assisted by an auxiliary system. The optimal success probability is found to be benefited by initial intrinsic coherence, but no extra one is required. The transformations among different contributions of intrinsic coherence are necessary in this procedure, which increase with the overlap between the states to recognize. Such state discrimination is a key step of the probabilistic teleportation protocol. Entanglement of the quantum channel decreases the coherence characterizing the reliance on an ancilla., Comment: 6 pages with 4 figures
- Published
- 2016
- Full Text
- View/download PDF
41. Aluminium-phosphorus interactions in plants growing on acid soils: does phosphorus always alleviate aluminium toxicity?
- Author
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Ren Fang Shen, Fu Lin Zhang, Qi Ming Zhang, Xiao Ying Dong, Qing Bin Sun, and Rong Fu Chen
- Subjects
Nutrition and Dietetics ,Phosphorus ,chemistry.chemical_element ,Soil chemistry ,Phosphorus metabolism ,chemistry ,Agronomy ,Aluminium ,Molar ratio ,Toxicity ,Soil water ,Botany ,Phytotoxicity ,Agronomy and Crop Science ,Food Science ,Biotechnology - Abstract
Aluminium (Al) toxicity and phosphorus (P) deficiency are considered to be the main constraints for crop production in acid soils, which are widely distributed in tropical and subtropical regions. Conventionally, P addition is regarded as capable of alleviating Al toxicity in plants. However, this field is still rife with unsubstantiated theories, especially for different plant species growing on acid soils. In this review, the responses of plants to different methods of Al-P treatments are briefly summarized, and possible reasons are proposed by considering recent results from our laboratory. It is shown that: (1) long-term Al-P alternate treatment is advantageous for studying Al-P interactions in plants; (2) under the long-term Al-P alternate treatment, the roles of P in Al phytotoxicity might be associated with the Al resistance capability and P use efficiency of the plant, and a P/Al molar ratio exceeding 5 in roots may be the threshold of P alleviating Al toxicity based on the calculation of the tested plants; (3) in acid soils, P application may be effective only after Al stress is overcome for Al-sensitive species. Thus it is concluded that P application does not always alleviate Al toxicity under long-term Al-P alternate treatment.
- Published
- 2011
42. Super fidelity and related metrics
- Author
-
Jing-Ling Chen, Zhi-Hua Chen, Zhi-Hao Ma, and Fu-Lin Zhang
- Subjects
Physics ,Quantum network ,Theoretical computer science ,metric ,QC1-999 ,General Physics and Astronomy ,Quantum channel ,Quantum capacity ,super-fidelity ,Open quantum system ,Quantum mechanics ,Metric (mathematics) ,Trace distance ,quantum state ,Fidelity of quantum states ,Quantum information - Abstract
We report a new metric of quantum states. This metric is built up from super-fidelity, which has a deep connection with the Uhlmann-Jozsa fidelity and plays an important role in quantum information processing. We find that the new metric possesses some interesting properties.
- Published
- 2011
43. Perturbative Treatment for Stationary State of Local Master Equation
- Author
-
Fu-Lin Zhang and Jian-Ying Du
- Subjects
Coupling ,Physics ,Quantum Physics ,Physics and Astronomy (miscellaneous) ,FOS: Physical sciences ,01 natural sciences ,Unitary state ,Open system (systems theory) ,010305 fluids & plasmas ,Simple (abstract algebra) ,0103 physical sciences ,Master equation ,Statistical physics ,Quantum Physics (quant-ph) ,010306 general physics ,Quantum ,Stationary state ,Coherence (physics) - Abstract
The local approach to construct master equation for a composite open system with a weak internal coupling is simple and seems reasonable. However, it is thermodynamic consistent only when the subsystems are resonantly coupled. Efforts are being made to understand the inconsistency and test the validity of the local master equation. We present a perturbative method to solve the steady-state solutions of linear local master equations, which are demonstrated by two simple models. The solving process shows the stationary state as the result of competition between incoherent operations and the unitary creating quantum coherence, and consequently relate quantum coherence with thermodynamic consistency., Comment: 5 pages, no fig
- Published
- 2018
44. Bounds of concurrence and their relation with fidelity and frontier states
- Author
-
Zhi-Hao Ma, Dong-Ling Deng, Jing-Ling Chen, and Fu-Lin Zhang
- Subjects
Physics ,Discrete mathematics ,Quantum Physics ,Measurement theory ,media_common.quotation_subject ,FOS: Physical sciences ,General Physics and Astronomy ,Fidelity ,Concurrence ,Quantum information ,Quantum Physics (quant-ph) ,Upper and lower bounds ,media_common - Abstract
The bounds of concurrence in [F. Mintert and A. Buchleitner, Phys. Rev. Lett. 98 (2007) 140505] and [C. Zhang \textit{et. al.}, Phys. Rev. A 78 (2008) 042308] are proved by using two properties of the fidelity. In two-qubit systems, for a given value of concurrence, the states achieving the maximal upper bound, the minimal lower bound or the maximal difference upper-lower bound are determined analytically.
- Published
- 2009
45. Influence of arbitrary magnetic field on entanglement in Heisenberg XXZ model
- Author
-
Jin-Hua Zhang, Mai-Lin Liang, and Fu-Lin Zhang
- Subjects
Physics ,Field (physics) ,Condensed matter physics ,Heisenberg model ,Quantum Physics ,Quantum entanglement ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,Magnetic field ,Ferromagnetism ,Qubit ,Quantum mechanics ,Antiferromagnetism ,Condensed Matter::Strongly Correlated Electrons ,Electrical and Electronic Engineering ,Physical and Theoretical Chemistry ,Quantum computer - Abstract
Thermal entanglement of the two-qubit XXZ model under magnetic fields in arbitrary directions is studied. Both the uniform and nonuniform fields are addressed. For the ferromagnetic case, a magnetic field perpendicular to the z-axis helps to enhance the entanglement or slows down the decrease of the entanglement. For the antiferromagnetic case, there is the revival phenomenon when the magnetic field is uniform and no such phenomenon when the field is uniform in the z-direction and a staggered type in the x-axis.
- Published
- 2007
46. New forms of wavefunctions for the isotropic harmonic oscillator in a time-dependent magnetic field
- Author
-
Mai-Lin Liang and Fu-Lin Zhang
- Subjects
Physics ,Quantum harmonic oscillator ,Quantum mechanics ,Anharmonicity ,Creation and annihilation operators ,Correspondence principle ,Coherent states ,Unitary transformation ,Condensed Matter Physics ,Mathematical Physics ,Atomic and Molecular Physics, and Optics ,Harmonic oscillator ,Squeezed coherent state - Abstract
After a unitary transformation, exact wavefunctions of the time-dependent two-dimensional harmonic oscillator in a time-dependent magnetic field are written in the form of the product of two one-dimensional time-dependent harmonic oscillators in the (x, py) representation. Applying the Heisenberg correspondence principle (HCP) to the system, the exact classical solution is obtained from the quantum matrix elements. Meanwhile, the coherent state is discussed.
- Published
- 2006
47. Sequential state discrimination and requirement of quantum dissonance
- Author
-
Jing-Ling Chen, Fu-Lin Zhang, Chao-Qian Pang, Mai-Lin Liang, and Li-Fang Xu
- Subjects
Physics ,Discrete mathematics ,Quantum Physics ,Quantum discord ,FOS: Physical sciences ,State (functional analysis) ,Quantum entanglement ,Atomic and Molecular Physics, and Optics ,Measurement theory ,Auxiliary system ,Qubit ,Cognitive dissonance ,Quantum Physics (quant-ph) ,Quantum - Abstract
We study the procedure for sequential unambiguous state discrimination. A qubit is prepared in one of two possible states, and measured by two observers Bob and Charlie sequentially. A necessary condition for the state to be unambiguously discriminated by Charlie is the absence of entanglement between the principal qubit, prepared by Alice, and Bob's auxiliary system. In general, the procedure for both Bob and Charlie to recognize between two nonorthogonal states conclusively relies on the availability of quantum discord which is precisely the quantum dissonance when the entanglement is absent. In Bob's measurement, the left discord is positively correlated with the information extracted by Bob, and the right discord enhances the information left to Charlie. When their product achieves its maximum the probability for both Bob and Charlie to identify the state achieves its optimal value., 4.5 pages, 3 figures
- Published
- 2013
48. Linear response of tripartite entanglement to infinitesimal noise
- Author
-
Jing-Ling Chen and Fu-Lin Zhang
- Subjects
Physics ,Coherence time ,Quantum Physics ,Quantum decoherence ,General Physics and Astronomy ,FOS: Physical sciences ,State (functional analysis) ,Quantum entanglement ,Noise (electronics) ,Upper and lower bounds ,Multipartite ,Quantum mechanics ,Quantum system ,Quantum Physics (quant-ph) - Abstract
Recent experimental progress in prolonging the coherence time of a quantum system prompts us to explore the behavior of quantum entanglement at the beginning of the decoherence process. The response of the entanglement under an infinitesimal noise can serve as a signature of the robustness of entangled states. A crucial problem of this topic in multipartite systems is to compute the degree of entanglement in a mixed state. We find a family of global noise in three-qubit systems, which is composed of four W states. Under its influence, the linear response of the tripartite entanglement of a symmetrical three-qubit pure state is studied. A lower bound of the linear response is found to depend completely on the initial tripartite and bipartite entanglement. This result shows that the decay of tripartite entanglement is hastened by the bipartite one., 5 pages,1 figure. Accepted by Annals of Physics
- Published
- 2013
49. Dirac equation with a magnetic field in 3D non-commutative phase space
- Author
-
Rui-Lin Yang, Mai-Lin Liang, Fu-Lin Zhang, and Ya-Bin Zhang
- Subjects
Physics ,Nuclear and High Energy Physics ,Quantum Physics ,Plane (geometry) ,FOS: Physical sciences ,Astronomy and Astrophysics ,Noncommutative geometry ,Classical limit ,Magnetic field ,Momentum ,symbols.namesake ,Classical mechanics ,Operator (computer programming) ,Phase space ,Dirac equation ,symbols ,Quantum Physics (quant-ph) ,Instrumentation - Abstract
For a spin-1/2 particle moving in a background magnetic field in noncommutative phase space, Dirac equation is solved when the particle is allowed to move off the plane that the magnetic field is perpendicular to. It is shown that the motion of the charged particle along the magnetic field has the effect to increase the magnetic field. In the classical limit, matrix elements of the velocity operator related to the probability give a clear physical picture: Along an effective magnetic field the mechanical momentum is conserved and the motion perpendicular to the effective magnetic field follows a round orbit. If using the velocity operator defined by the coordinate operators, the motion becomes complicated., 10 pages. Submitted to 'Chinese Physics C'
- Published
- 2013
50. Higgs algebraic symmetry of screened system in a spherical geometry
- Author
-
Rui-Juan Gu, Jing-Ling Chen, Fu-Lin Zhang, and Yan Li
- Subjects
Physics ,Angular momentum ,Quantum Physics ,Physics and Astronomy (miscellaneous) ,FOS: Physical sciences ,Mathematical Physics (math-ph) ,Symmetry group ,Symmetry (physics) ,Homogeneous space ,Higgs boson ,Coulomb ,Tensor ,Astrophysics::Earth and Planetary Astrophysics ,Quantum Physics (quant-ph) ,Eigenvalues and eigenvectors ,Mathematical Physics ,Mathematical physics - Abstract
The orbits and the dynamical symmetries for the screened Coulomb potentials and isotropic harmonic oscillators have been studied by Wu and Zeng [Z. B. Wu and J. Y. Zeng, Phys. Rev. A 62,032509 (2000)]. We find the similar properties in the responding systems in a spherical space, whose dynamical symmetries are described by Higgs Algebra. There exists a conserved aphelion and perihelion vector, which, together with angular momentum, constitute the generators of the geometrical symmetry group at the aphelia and perihelia points $(\dot{r}=0)$., 8 pages, 1 fig
- Published
- 2012
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