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A tunable multiple windows optomechanically induced transparency (OMIT) with a squeezed field is investigated in a system consisting of an optomechanical cavity coupled to a charged nanomechanical resonator (NAMR) via Coulomb interaction. Such a multiple OMIT can be achieved by adjusting the frequency of the charged NAMR and can be observed even with a single-photon squeezed field. In addition, this multiple OMIT for the quantized fields can be robust against cavity decay and environmental temperature. Specifically, the model under our consideration might be applied to precision measurement the frequency difference of two NAMRs within the reach of current techniques.

Local CO 2 laser processing was reported to effectively mitigate the laser-induced damage growth of 3ω fused silica optics. Herein, combined with the experimental observations, the light intensification of repaired damage sites irradiated at different laser powers and beam sizes were revealed by using three-dimensional finite-difference time-domain method. Two typical nonideal repaired damage sites, with raised rim as well as with concave rim, were discussed. Numerical simulation results show that crater with raised rim generate much greater modulation than the other one. With the laser beam size increasing, the modulation for raised rim crater monotonously increases, while the modulation for concave rim crater increases firstly and then keeps decreasing in the following. On the other hand, the light intensification undergoes decreasing firstly and then increasing when laser power increases. Under the same parameters, it is shown that the modulation of the ideal Gaussian profile is the weakest of all. For the normal incident irradiation at 355 nm laser, the light intensity enhancement factors of the raised and concave rim can be as high as 7.13 and 25.04, respectively. To effectively arrest the damage growth and prolong service life of the optics, Gaussian-typed repaired damage sites should be introduced considering optics recycling.

Local CO 2 laser processing has been proved to be an effective method for mitigating damage growth of 3ω fused silica optics. For nonideal repaired damage site, the laser intensification induced by bubbles may result in near-field damage when ultraviolet laser transmitting through. Three-dimensional finite-difference time-domain method is employed to quantify the electric-field around aforementioned bubbles in the vicinity of rear subsurface. Result shows that the modulation is more remarkable between neighbors than other region. The intensification increases firstly and then decreases with the increase of its depth and gap, and it monotonously ascends with increasing its size. With increasing its number at the same plane, a larger modulation acquired. Comparing non-coplanar with coplanar 4 bubbles, the latter generate much greater modulation.

We study the tunable optomechanically induced absorption (OMIA) with the quantized field in the system, which consists of a driven cavity and a mechanical resonator with a super-conducting charge qubit via Jaynes-Cummings interaction. Such a OMIA can be achieved by controlling the strength of the Jaynes-Cummings interaction. Moreover, our work shows this OMIA for the quantized fields can be robust against cavity decay in somehow. With the combination of optomechanically induced transparency (OMIT), our proposal may have paved a new avenue towards quantum photon router.

I–III–VI2 chalcopyrite compounds (I = Cu or Ag; III = Al, Ga, or In; VI = S, Se, or Te), especially sulfides and selelides, were studied as the promising photocathodes for water splitting. In this work, tellurides with a proper band gap [i.e. CuAlTe2 (2.06 eV) and AgAlTe2 (2.27 eV)] had been investigated as the photocathode candidates by our first-principles calculations. Our results show that the band edge positions of AgAlTe2 straddle the water redox potentials. In combination with the suitable band gap energy and light carrier effective masses along [001]-direction, AgAlTe2 has the capacity of being a good candidate for water splitting. Moreover, to increase the absorbing ability on visible light, Ga-doping can adjust the band gap of AgAlTe2 to an appropriate value and remain the reasonable band edge positions of AgAlTe2, which is suggested as an effective approach to optimize its electronic structure for water splitting.

The parity symmetry and parity breaking in the super-Ohmic spin-boson model (SBM) is studied by using the coherent-state approach. We show that the parity symmetry is broken as well as the scaling behavior of the ground state by introducing a bias, and then it can be restored by involving an additional spin into the SBM to couple with the original spin by an Ising interaction. The rule can be found that the parity symmetry is broken by introducing a bias and then restored by adding new degrees of freedom.

Protection of entanglement from disturbance of the environment is an essential task in quantum information processing. We examine the validity and limitation of the weak measurement and reversal (WMR) operation in the protection of distributed entanglement from various decoherence sources. Since the entanglement variation can be investigated analytically for an arbitrarily entangled bipartite pure state under three kinds of typical noisy quantum channels, we show explicitly that the WMR operation indeed helps for protecting distributed entanglement from amplitude damping and phase damping, but not for depolarizing. Experimental feasibility for testing our results is discussed using current laboratory techniques.

Aiming at the importance of sampling in CCD photoelectric imaging system, the content is studied by us in detail. Firstly, its basic principle is analyzed, and the simple physics explanation and formula deduction are given, and the spectrum expression is obtained. Secondly, the cause of lack sampling is analysed. Finally, the results of experiment verify the correctness of theory analysis.

Until now, no effective method to measure CCD photoelectric parameters. To solve the problem, a novel measurement method that combines hardware with software is proposed, and it can let hardware and software collaborate with each other to finish assignment together. Firstly, the ideal relation between output voltage and input exposure quantity of CCD is given. Secondly, some main photoelectric parameters of CCD are elaborated. Then based on the principle, test system of CCD photoelectric parameters that combines hardware with software is designed. Lastly, the real relation between output voltage and input exposure quantity of CCD is given, and the test results of experiment of each photoelectric parameter are obtained according to the relation. What’s more, analysis and comparison of the results of the experiment are given in this paper. The method is reliable and the precision is high in the experiment.

The paper investigated the effect of chemical etching and temperature on the optical properties and microstructures of porous silicon layer fabricated by the pulse electrochemically etching by means of the reflectance spectroscopy and photoluminescence spectroscopy. The relationship between the optical thickness (nd) and refractive index n of porous silicon layer and the chemical etching time and temperature has been detailedly studied. With increasing the chemical etching times, the reflectance spectra exhibit the more intense interference oscillations, which mean the uniformity and interface smoothness of porous silicon layers become better, meanwhile, results in decreasing the optical thickness and refractive index, indicating a higher porosity. Moreover, the intensity of photoluminescence spectra increases, and the envelope curves of photoluminescence spectra exhibit a trend of red-shift, which implied the average diameter of silicon nanocrystallite became larger. The chemical etching rate of the optical thickness intensely increases with the chemical etching temperature.

By solving the master equation of Redfield form, we investigate the decoherence of a reduced open-driven qubit. It is shown that when the driving field has not too large frequency to compare to the Rabi frequency of the qubit system, the decoherence of the qubit is affected by the amplitude but not by the frequency of the driving field. We can prolong the decoherence time of the qubit as we choose an appropriate driving field to operate the qubit.

We present two schemes for efficient implementation of a nonlocal gate with nonmaximal entanglement. The main strategy of the schemes is local conversion of pure states, which consists of a generalized measurement described by a positive operator-valued measure (POVM), one-way classical communication, and corresponding unitary operations. First, we discuss the way to generate determinately the nonlocal gate via any pure shared entangled state combined with entanglement-assistance. Then we propose the other way to generate probabilistically the nonlocal gate via any pure entangled state with the aid of ancillary particles.

Noisy entangled resource and non-standard teleportation operations result in imperfect teleportation. In this paper, we derive an explicit expression for the output states of imperfect teleportation processes, thereby establishing a correspondence between teleportation and quantum channels. This result offers a different insight into teleportation. Also, it enables us to derive an expression for the fidelity of teleportation. Our results analytically reveal the dependence of the output states and the fidelity on the entangled resource and teleportation operations. The Nielsen–Caves teleportation formalism is used in the derivation.

Teleportation is viewed as a quantum channel. We present an explicit expression for the general teleportation channel in the Kraus decomposition form. We then analyse optimal teleportation procedures for a noisy entangled resource, Bell measurement by the sender and arbitrary operations by the receiver. Our general result allows us to derive the corresponding quantum channel and fidelity, thereby enabling us to formulate the fidelity-based optimization problem and to conclude that this is a problem of semidefinite programming. We offer an alternative viewpoint on optimal teleportation, namely one can perform corrective operations at the receiver's side instead of first manipulating entanglement, and we give an optimal teleportation strategy.

Chronic active Epstein-Barr virus infection (CAEBV) represents a new subtype of lymphoproliferative disorders characterized by high morbidity and mortality rates and often leads to malignant transformation of infected cells. Efficient therapeutic strategies are presently unavailable; therefore, the development of therapies to prevent CAEBV-mediated transformation and disease progression is crucial. Here, we used microarray analysis and luciferase reporter assays to reveal the potential role of activated nuclear factor kappa B (NF-kB) in T cell type of-CAEBV infection. Using a series of cellular and molecular experiments, we demonstrated that dehydroxymethylepoxyquinomicin (DHMEQ), a novel NF-kB inhibitor, can selectively induce apoptosis in SNT-16 cells infected with CAEBV. Mechanistic studies suggested that DHMEQ induces SNT-16 cell apoptosis through NF-kB inhibition coupled with oxidative stress generation. Thus, activated NF-kB could be a new target for CAEBV therapeutics. Owing to its selective targeting ability, DHMEQ may be a candidate for a novel therapeutic regimen to control the progression of CAEBV infections.

A tunable double optomechanically induced transparency (OMIT) with a squeezed field is investigated in a system consisting of an optomechanical cavity coupled to a charged nanomechanical resonator via Coulomb interaction. Such a double OMIT can be achieved by adjusting the strength of the Coulomb interaction, and observed even with a single-photon squeezed field at finite temperature. Since it is robust against the cavity decay, but very sensitive to some parameters, such as the environmental temperature, the model under our consideration can be applied as a quantum thermometer for precision measurement of the environmental temperature within the reach of current techniques., Comment: 8 pages, 6 figures, to be published in Phys. Rev. A

We introduce an alternative method based on local quantum uncertainty to measure non-Markovianity for an open quantum system. The local quantum uncertainty proposed by Girolami $et al$. [Phys. Rev. Lett. 110, 240402 (2013)] is defined by the minimum skew information from a local measurement perspective. The measure effectively captures the characteristics of non-Markovianity and has a clearly physical interpretation: in correlated bipartite systems, the non-Markovian (Markovian) process of a considered open subsystem corresponds to the increase (decrease) of quantum uncertainty of local observables of another measured free subsystem. Then the local quantum uncertainty is further discussed by carefully handling the square root of the density operator for the bipartite $2\ensuremath{\bigotimes}d$ systems. Specifically, for a two-qubit system we give an explicit expression of the local quantum uncertainty. Furthermore, by applying the measure to three typical non-Markovian noise channels, we find that the conditions of detecting the non-Markovianity are consistent with the results of existing measures for non-Markovianity, i.e., information backflow and divisibility.

Using the weak measurement (WM) and quantum measurement reversal (QMR) approach, robust state transfer and entanglement distribution can be realized in the spin-$\frac{1}{2}$ Heisenberg chain. We find that the ultrahigh fidelity and long distance of quantum state transfer with certain success probability can be obtained using proper WM and QMR, i.e., the average fidelity of a general pure state from $80%$ to almost $100%$, which is almost size independent. We also find that the distance and quality of entanglement distribution for the Bell state and the general Werner mixed state can be obviously improved by the WM and QMR approach.

Ethnopharmacological relevance The rhizome of Atractylodes macrocephala (Compositae) is one of the most well-known traditional Chinese medicine in China, Japan and Korea, which has a long history of use for the treatment of splenic asthenia, edema, anorexia, and excessive perspiration, etc . As active compounds of anti-inflammatory activity of this medicinal plant have not been fully elucidated, the aim of this study was to isolate and identify the active constituents inhibiting nitric oxide (NO) production from the rhizomes of A. macrocephala . Materials and methods Inhibitory activity against NO production in lipopolysaccharide-activated RAW264.7 macrophages was evaluated by Griess reaction. Fifteen polyacetylenes were isolated from the active ethyl acetate extract using activity-guided screening. The structures of all compounds were elucidated by spectroscopic methods and comparison with published data. The compounds were further tested for their inhibitory activity against NO production. Results Seven new polyacetylenes, named atractylodemaynes A–G ( 1 – 7 ), along with eight known ones ( 8 – 15 ) were isolated. Compound 14 was isolated for the first time from the rhizomes of A. macrocephala . The study showed that the tested compounds exhibited inhibitory activity against NO production in a dose-dependent manner. Among them, compounds 10 , 11 and 12 had relatively stronger inhibitory effect with IC 50 values of 28, 23 and 19 μM, respectively. Conclusion The results demonstrated that the polyacetylenes might greatly contribute to the anti-inflammatory activity of the rhizomes of A. macrocephala .

The speed of evolution of a qubit undergoing a nonequilibrium environment with spectral density of general ohmic form is investigated. First we reveal non-Markovianity of the model, and find that the non-Markovianity quantified by information backflow of Breuer et al. [Phys. Rev. Lett. 103 210401 (2009)] displays a nonmonotonic behavior for different values of the ohmicity parameter s in fixed other parameters and the maximal non-Markovianity can be achieved at a specified value s. We also find that the non-Markovianity displays a nonmonotonic behavior with the change of a phase control parameter. Then we further discuss the relationship between quantum speed limit (QSL) time and non-Markovianity of the open-qubit system for any initial states including pure and mixed states. By investigation, we find that the QSL time of a qubit with any initial states can be expressed by a simple factorization law: the QSL time of a qubit with any qubit-initial states are equal to the product of the coherence of the initial state and the QSL time of maximally coherent states, where the QSL time of the maximally coherent states are jointly determined by the non-Markovianity, decoherence factor and a given driving time. Moreover, we also find that the speed of quantum evolution can be obviously accelerated in the wide range of the ohmicity parameter, i.e., from sub-Ohmic to Ohmic and super-Ohmic cases, which is different from the thermal equilibrium environment case.

Severe combined immunodeficiency (SCID), a rare type of genetic associated immune disorder, is poorly characterized in mainland China. We retrospectively reviewed 44 patients with SCID who received treatment from 2004 to 2011 in Shanghai, China, and herein summarize their clinical manifestations and immunological and preliminary genetic features. The male-to-female ratio was 10:1. Twenty five patients presented with X-SCID symptoms. Only one patient was diagnosed before the onset of symptoms due to positive family history. The mean time of delay in the diagnosis of X-SCID was 2.69 months (range, 0.5–8.67). Thirty-seven of the 44 patients died by the end of 2011 with the mean age of death being 7.87 months (range, 1.33–31). Six patients received hematopoietic stem cell transplantation (HSCT); only one of them survived, who was transplanted twice. The time between onset and death was shorter in the HSCT-treated group compared with the untreated group (2.87 ± 1.28 and 3.34 ± 0.59 months, respectively), probably due to active infections during transplantation. Bacillus Calmette–Guerin (BCG) complications occurred in 14 of the 34 patients who received BCG vaccination. Transfusion-induced graft-versus-host disease occurred in 5 patients. Total 20 mutations in interleukin-2 receptor subunit gamma (IL2RG) were identified in 22 patients, including 11 novel mutations. Most patients were misdiagnosed before referred to our SCID Center. Therefore, establishing more diagnostic centers dedicated to the care of PID and accessible by primary immunodeficiency patients will facilitate early, correct diagnosis and better care of SCID in China.

We present two purification schemes for nonmaximally entangled states. We first show that two parties, Alice and Bob, start with shared less-entangled three-particle states to probabilistically produce a three-particle Greenberger–Horne–Zeilinger state by Bell state measurements and positve operator valued measure (POVM) or a unitary transformation. Then, by a straightforward generalization of the schemes, the purification of a multi-particle entangled state can be realized.

Four new triterpene saponins, ginsenosides Rh(14)-Rh(17)(1- 4), along with two known compounds, 20(S)-ginsenoside Rg₂ and dammar-(E)-20(22),24-diene-3 β,6 α,12 β-triol, were isolated from the stems and leaves of Panax ginseng. The structures of the new compounds were elucidated as 3 β,6 α,12 β,24 ξ-tetrahydroxy-dammar-(E)-20(22),25-diene 6- O- α- L-rhamnopyranosyl-(1 → 2)- β-D-glucopyranoside (1), 3 β,12 β,24 ξ-trihydroxy-dammar-(E)-20(22),25-diene 3- O- β- D-glucopyranosyl-(1 → 2)- β-D-glucopyranoside (2), 3 β,6 α,12 β-trihydroxy-dammar-(E)-20(22),24-diene 3-O-β-D-glucopyranoside (3), and 3-oxo-6 α,12 β,20(S)-trihydroxy-dammar-24-ene 6-O-α-L-rhamnopyranosyl-(1 → 2)-β-D-glucopyranoside (4) by means of extensive spectroscopic and chemical methods, respectively. The isolated compounds were tested for IN VITRO cytotoxicity against HL-60 cells.

The high p-type conductivity in Cu-excess CuAlS2 reported from a recent experimental paper is not well understood as it is not supported by earlier theoretical studies. We found that Cu can be heavily doped at the Al site and can form compensated defect bands to shift up the valence band, leading to shallow acceptor levels under a Cu-excess condition. In particular, Zn doping at the Al site in Cu-excess CuAlS2 has been suggested as a promising approach to improving the p-type conductivity in Cu-excess CuAlS2.

To explore the therapeutic mechanisms of interferon-beta (IFN-beta) and intravenous immunoglobulin (IVIG) for experimental peripheral neuropathy induced by Campilobacter jejuni (Cj) lipopolysaccharide (LPS).Forty healthy Wistar rats weighing 205 - 230 g were divided into IFN-beta, IVIG, IFN-beta plus IVIG and control groups. After the immune neuropathy was induced in the rats by Cj LPS, IFN-beta (1.3 microg/kg) was given by subcutaneous injection to the rats every other day for 6 weeks; IVIG [400 mg/(kg x d)] was given to the rats for five days, every other week for two times and IFN-beta [1.3 microg/(kg x d)] and IVIG [400 mg/(kg x d)] were given to the rats on the same days. Meanwhile, the control group was given PBS. The sera were collected in the 2nd, 4th and 6th week after therapy, the titers of anti-GM(1) IgG, MMP-9 and TNF-alpha in sera of immunized rats were measured by ELISA; histological study of sciatic nerve was performed and IgG on sciatic nerve was detected by immunohistochemistry in the 6th week.(1) There were no significant differences in titers of anti-GM(1) IgG, MMP-9 and TNF-alpha among the 3 therapeutic groups and control group after therapy for 2 weeks (P0.05). (2) The titers of anti- GM(1) IgG, MMP-9 or TNF-alpha in the control group were much higher than those of the IFN-beta group, the IVIG group or the IFN-beta and IVIG group after therapy for 4 weeks (P0.01) and there were no significant differences in titers of antibody among the 3 therapeutic groups (P0.05); the titers of MMP-9 or TNF-alpha in the IFN-beta and IVIG group were lower than those of the IFN-beta group or the IVIG group (P0.05). (3) The titers of anti-GM(1) IgG, MMP-9 or TNF-alpha in the control group were much higher than those of the IFN-beta group, the IVIG group or the IFN-beta with IVIG group after therapy for 6 weeks (P0.01); the IFN-beta with IVIG group had much lower levels of all indexes than the IFN-beta group or the IVIG group (P0.01).IFN-beta and IVIG showed therapeutic effects on immune peripheral neuropathy through inhibiting the humoral and cellular immunity simultaneously in the peripheral neuropathy induced by CJ LPS, treatment with combined IFN-beta and IVIG was more effective.

Decoherence suppression from disturbance of the environment is an essential task in quantum information processing. We investigate decoherence suppression of a qutrit system interacting with a zero-temperature reservoir with both spontaneous emission and dephasing by employing the weak measurement and reversal (WMR) operation. We find that the qutrit decoherence can be efficiently suppressed by solving the master equation of the qutrit system. In particular, WMR can completely suppress the decoherence in the case of strong decay rates.

The enhancement of the precision of phase estimation in quantum metrology is investigated by employing weak measurement (WM) and quantum measurement reversal (QMR). We derive the exact expressions of the optimal quantum Fisher information (QFI) and success probability of phase estimation for an exactly solving model consisting of a qubit interacting with a structured reservoir. We show that the QFI can be obviously enhanced by means of the WM and QMR in different regimes. In addition, we also show that the magnitude of the decoherence involved in the WM and QMR can be a general complex number, which extends the applicable scope of the WM and QMR approach.

Most reported p-type transparent conductive materials are Cu-based compounds such as CuAlO2 and CuCrO2. Here, we report that compounds based on ns2 cations with low binding energy can also possess high valence band maximum, which is crucial for the p-type doping according to the doping limit rules. In particular, CsGeCl3, a compound with valence band maximum from ns2 cations, is predicted as a promising p-type transparent conductive material by first-principles calculations. Our results show that the p-type defect Ge vacancy dominates its intrinsic defects with a shallow transition level, and the calculated hole effective masses are low in CsGeCl3.

The effect of weak measurement (WM) and quantum measurement reversal (QMR) on the entanglement transfer in two parallel Heisenberg spin chains is investigated. We find that the entanglement transfer can be enhanced by the WM and QMR control for different N (N is the length of each spin chain) and m (m denotes the mth spin pair). More interestingly, we also find that, in the thermodynamic limit where the so-called phase-shift control is invalid, the WM and QMR control is instead very effective. So this investigation indicates that the WM and QMR approach has potential applications in quantum information processing based on the spin chain.

The electronic structure of AgGaSe2 has been investigated as a photocatalyst candidate by first-principles calculation. Our results demonstrate that the band edge positions of bulk AgGaSe2 straddle the water redox potentials. From the band offset calculation, we find that Al-doping of AgGaSe2 shifts the conduction band minimum upwards, whereas Cu-doping of AgGaSe2 shifts the valence band maximum upwards. By (Ag, Cu)(Ga, Al)Se2 alloying one can thereby tailor both the band edge positions and the band gap energy, and this effect provides an approach to optimize the band properties for overall water splitting. Moreover, AgGaSe2 forms a suitable junction with CuGaSe2 with a type-II band offset, which facilitates electron-hole separation. The AgGaSe2 and CuGaSe2 junction can be designed as a tandem photoelectrochemical device to improve the photocatalytic properties of the system.

Through comparisons with an entanglement breaking (EB) channel, we characterize the local quantum channels that destroy quantum correlations, especially for quantum discord, and give a detailed description of a discord-breaking (DB) channel. We prove that the quantum discord can be broken if and only if the local quantum channel is a commutativity-creating (CoC) channel. Then we show which kind of channels is a CoC channel, and address the relation between EB and DB channels. Furthermore we apply our results to three typical noise channels.

γ-CuI has attracted considerable attention recently as a p-type transparent conductive material. In this paper, we have investigated the hole effective mass, intrinsic defects and group VI-A impurities in γ-CuI by first-principles calculations. We found that the hole effective mass of γ-CuI is light, in line with the high p-type mobility observed in experiments. The p-type conductance is expected to originate from Cu vacancies, which have a low formation energy with no significant n-type compensating defects. The relative high transition level of Cu vacancy, however, may lead to a low hole concentration in the γ-CuI sample. Additionally, no shallow transition levels were found in γ-CuI with substitutional group VI-A impurities at I sites.

CuAlS2 has attracted much attention recently as a p-type transparent conductive material. In this paper, we investigate the site preference of substitutional Be in CuAlS2 and the transition level of BeAl using the first-principles calculation. We find that Be would be doped effectively at Al sites in CuAlS2 as a good p-type dopant. In addition, we speculate that Be–Mg or Be–Zn codoped CuAlS2 could have a mobility enhancement and thus a good p-type conductivity due to low lattice distortion.

We have investigated the intrinsic defects, and Mg, Zn impurities in CuAlS2, as well as their induced carrier concentrations using the first-principles calculations. We find that p-type conductivity could be dominated by the intrinsic defects VCu, CuAl or the doping defects ZnAl, MgAl in different samples. Although vacancy Cu is an important acceptor in CuAlS2, a Cu-deficient sample is not the best for p-type conductivity due to the compensation from AlCu defects. In fact, our results indicate that Zn is the best choice for p-type doping for CuAlS2, in particular under Cu-rich and Al-poor condition, which is in line with the experimental results. The main difference in carrier concentration between theory and experiment is expected to have originated from the multiphase of the samples prepared in experiments, instead of a single crystal. We also find that there is no remarkable difference in the effective mass in samples dominated by different defects, such as CuAl, MgAl, ZnAl and Cu vacancy. The significant difference in the experimentally observed hole mobility may be dominated by their mean free time τ p .