Search

In strong field ionization, the pump pulse not only photoionizes the molecule, but also drives efficient population exchanges between its ionic ground and excited states. In this study, we investigate the population dynamics after strong field molecular photoionization, using angular distribution of dissociative fragments. Our results reveal that the first and third order processes of the post-ionization population redistribution mechanism (PPRM) in the ion can be disentangled and classified by its angle-resolved kinetic energy release (KER) spectra. We demonstrate that the imprints of PPRM in the KER spectra can be used to determine the branching ratio of the population exchange pathways of different orders, by exploiting the pump-intensity-dependent variation of the spectra.

We analyze the nucleon structure of the α-decaying nucleus to see if it can be visible in the experimental bremsstrahlung spectra of the emitted photons which accompany such a decay. We develop a new formalism of the bremsstrahlung model taking into account the distribution of nucleons in the α-decaying nuclear system. We conclude the following. (1) After inclusion of the nucleon structure in the model the calculated bremsstrahlung spectrum is changed very slowly for a majority of the α-decaying nuclei. However, we have observed that visible changes really exist for the 106Te nucleus (Qα= 4.29 MeV, T1/2 = 70 μs) even for the energy of the emitted photons up to 1 MeV. This nucleus is a good candidate for future experimental study of this task. (2) Inclusion of the nucleon structure in the model increases the bremsstrahlung probability of the emitted photons. (3) We find the following tendencies for obtaining the nuclei, which have bremsstrahlung spectra more sensitive to the nucleon structure: (a) direction to nuclei with smaller Z and (b) direction to nuclei with larger Qα values. [ABSTRACT FROM AUTHOR]

A new approach is presented to determine the proton-nucleus interactions from the analysis of the accompanying photon bremsstrahlung. We study the scattering of p +208Pb at the proton incident energies of 140 and 145 MeV, and the scattering of p +12C, p +58Ni, p +107Ag, and p +197Au at the proton incident energy of 190 MeV. The model determines contributions of the coherent emission (formed by an interaction between the scattering proton and nucleus as a whole without the internal many-nucleon structure), incoherent emission (formed by interactions between the scattering proton and nucleus with the internal many-nucleon structure), and transition between them in dependence on the photon energy. The radius parameter of the proton-nucleus potential for these reactions is extracted from the experimental bremsstrahlung data analysis. We explain the hump-shaped plateau in the intermediate- and high-energy regions of the spectra by the essential presence of the incoherent emission, while at low energies the coherent emission predominates which produces the logarithmic shape spectrum. We provide our predictions (in absolute scale) for the angular distribution of the bremsstrahlung photons in order to test our model, results, and analysis in further experiments. [ABSTRACT FROM AUTHOR]

As an important degree of freedom (d.o.f.) in photonic integrated circuits, the orthogonal transverse mode provides a promising and flexible way to increase communication capability, for both classical and quantum information processing. To construct large-scale on-chip multimode multi-d.o.f.s quantum systems, a transverse mode-encoded controlled-NOT (CNOT) gate is necessary. Here, with the help of our new transverse mode-dependent directional coupler and attenuator, we demonstrate the first multimode implementation of a 2-qubit quantum gate. The ability of the gate is demonstrated by entangling two separated transverse mode qubits with an average fidelity of 0.89±0.02 and the achievement of 10 standard deviations of violations in the quantum nonlocality verification. In addition, a fidelity of 0.82±0.01 is obtained from quantum process tomography used to completely characterize the CNOT gate. Our work paves the way for universal transverse mode-encoded quantum operations and large-scale multimode multi-d.o.f.s quantum systems. [ABSTRACT FROM AUTHOR]

Incorporating the bolometric effect, the thermoelastic damping in a nanowaveguide resonator driven by an optical gradient force is investigated in this paper. Based on the Euler-Bernoulli beam theory, the governing equation of the optowaveguide resonator is derived by considering the complex distribution of injected optical power, which has significant influence on the thermoelastic damping. By solving the heat diffusion equation, the theoretical model of the thermoelastic damping is presented. In this model, the effects of injected optical power, representative temperatures, waveguide material, and geometries on the thermoelastic damping are studied and discussed respectively. The results show that the peak value of thermoelastic damping increases as the injected optical power is increasing within a low range. Hardly any changes exist for the intrinsic energy dissipation of different materials at higher injected optical power. When the environmental temperature falls in the range of 293-500 K, the thermoelastic damping increases slowly, and then drops down quickly as a function of the dimensionless frequency. However, the thermoelastic damping monotonically decreases when the representative temperature drops to lower than 293 K. In addition, the thermoelastic damping is found to be scale dependent, particularly with the effect of injected optical power. [ABSTRACT FROM AUTHOR]

One-dimensional valence bond solid (VBS) states represent the simplest symmetry-protected topological phases. We show that their ground state entanglement spectrum contains both topological and nontopological structures. For the SO(3) symmetric VBS states with odd-integer spins, the twofold topological degeneracy is associated with an underlying Z2 × Z2 symmetry that protects the corresponding topological phase. In general, for the SO(2S + 1) symmetric VBS states with integer spins S, the corresponding protecting symmetry is identified as the (Z2 x Z2)S symmetry, yielding the 2S-fold topological degeneracy. The topological degeneracy and associated protecting symmetry can be identified by a nonlocal unitary transformation, which changes the topological order of the VBS states into conventional ferromagnetic order. [ABSTRACT FROM AUTHOR]

We carefully consider the interplay between ferromagnetism and the Kondo screening effect in the conventional Kondo lattice systems at finite temperatures. Within an effective mean-field theory for small conduction electron densities, a complete phase diagram has been determined. In the ferromagnetic ordered phase, there is a characteristic temperature scale to indicate the presence of the Kondo screening effect. We further find two distinct ferromagnetic long-range ordered phases coexisting with the Kondo screening effect: spin fully polarized and partially polarized states. A continuous phase transition exists to separate the partially polarized ferromagnetic ordered phase from the paramagnetic heavy Fermi liquid phase. These results may be used to explain the weak ferromagnetism observed recently in the Kondo lattice materials. [ABSTRACT FROM AUTHOR]

We prove that the Kane-Mele-Hubbard model with purely imaginary next-nearest-neighbor hoppings has a particle-hole symmetry at half filling. Such a symmetry has interesting consequences including the absence of charge and spin currents along open edges, and the absence of the sign problem in the determinant quantum Monte Carlo simulations. Consequentially, the interplay between band topology and strong correlations can be studied at high numeric precisions. The process that the topological band insulator evolves into the antiferromagnetic Mott insulator as interaction strength increases is studied by calculating both the bulk and edge electronic properties. [ABSTRACT FROM AUTHOR]

The heavy Fermi liquid with short-range antiferromagnetic correlations is carefully considered in the two- dimensional Kondo-Heisenberg lattice model. As the ratio of the local Heisenberg superexchange JH to the Kondo coupling JK increases, the topology of the Fermi surface (FS) of the heavy quasiparticles changes: at JH/JK = 0.1055 a first-order quantum phase transition is identified, where a small FS circle begins to emerge within the large deformed FS circle centered at (π, π). When JH/JK = 0.1425, the two deformed FS circles intersect each other and then decompose into four kidneylike Fermi pockets via a second-order quantum phase transition. As JH/JK increases further, the Fermi pockets are shifted inward along the direction (π, π) to (π/2,π/2), and the resulting FS is consistent with that obtained recently using the cluster dynamic mean-field approach to the Kondo lattice model in the presence of the antiferromagnetic order. [ABSTRACT FROM AUTHOR]

We propose a one-dimensional quantum Heienberg spin-2 chain, which exhibits two topologically distinct valence bond solid states in two different solvable limits. We then construct the phase diagram and study the quantum phase transition between these two states using infinite time evolving block decimation algorithms. From the scaling relation between the entanglement entropy and the correlation length, we determine that the central charge for the underlying critical conformal field theory is around two. [ABSTRACT FROM AUTHOR]

Quantum target detection is an emerging application that utilizes entanglement to enhance the sensing of the presence of an object. Although several experimental demonstrations for certain situations have been reported recently, the single-shot detection limit imposed by the Helstrom limit has not been reached because of the unknown optimum measurements. Here we report an experimental demonstration of quantum target detection, also known as quantum illumination, in the single-photon limit. In our experiment, one photon of the maximally entangled photon pair is employed as the probe signal and the corresponding optimum measurement is implemented at the receiver. We explore the detection problem in different regions of the parameter space and verify that the quantum advantage exists even in a forbidden region of the conventional illumination, where all classical schemes become useless. Our results indicate that quantum illumination breaks the classical limit for up to 40%, while approaching the quantum limit imposed by the Helstrom limit. These results not only demonstrate the advantage of quantum illumination, but also manifest its valuable potential of target detection. [ABSTRACT FROM AUTHOR]

To build universal quantum computers, an essential step is to realize the so-called controlled-NOT (CNOT) gate. Quantum photonic integrated circuits are well recognized as an attractive technology offering great promise for achieving large-scale quantum information processing, due to the potential for high fidelity, high efficiency, and compact footprints. Here, we demonstrate a supercompact integrated quantum CNOT gate on silicon by using the concept of symmetry breaking of a six-channel waveguide superlattice. The present path-encoded quantum CNOT gate is implemented with a footprint of 4.8×4.45  μm² (∼3λ×3λ) as well as a high-process fidelity of ∼0.925 and a low excess loss of <0.2  dB. The footprint is shrunk significantly by ∼10 000 times compared to those previous results based on dielectric waveguides. This offers the possibility of realizing practical large-scale quantum information processes and paving the way to the applications across fundamental science and quantum technologies. [ABSTRACT FROM AUTHOR]

We report theoretical and experimental analyses of the thermal Hall conductivity in correlated systems. For both fermionic and bosonic excitations with nontrivial topology, we show that at "intermediate" temperatures, the thermal Hall conductivity exhibits an unexpected universal scaling with a simple exponential form. At low temperatures, it behaves differently and reflects the spectral properties of underlying excitations. Our predictions are examined as examples in two prototype compounds, the quantum paraelectric SrTiO3 and the spin-liquid compound RuCl3. The experimental data can be largely covered by our proposed minimal phenomenological model independent of microscopic details, revealing dominant bosonic contributions in SrTiO3 and gapped fermionic excitations in RuCl3. Our work establishes a phenomenological link between microscopic models and experimental data and provides a unified basis for analyzing the thermal Hall conductivity in correlated systems over a wide temperature region. [ABSTRACT FROM AUTHOR]

We investigate an idea of how to use analysis of bremsstrahlung photons to study the internal structure of a proton under nuclear reaction with a nucleus. A new model is constructed to describe bremsstrahlung emission of photons which accompanies the scattering of protons off nuclei. Our bremsstrahlung formalism uses a many-nucleon basis that allows us to analyze coherent and incoherent bremsstrahlung emissions. Because a scattered proton can be under the influence of strong forces and produces the largest bremsstrahlung contribution to the full spectrum, we focus on accurate determination of its quantum evolution in relation to the nucleus based on quantum mechanics. For this purpose, we generalize the Pauli equation with an interacting potential describing evolution of a fermion inside the strong field, including the electromagnetic form factors of nucleons based on deep inelastic scattering theory. Anomalous magnetic momenta of nucleons reinforce our motivation to develop such a formalism. The full bremsstrahlung spectrum in our model (after renormalization) is dependent on form factors of the scattered proton. In our calculations we choose the scattering of p + 197Au at a proton beam energy of 190 MeV, where experimental bremsstrahlung data were obtained with high accuracy. We show that the full bremsstrahlung spectrum is sensitive to the form factors of the scattered proton. In the limit without such form factors, we reconstruct our previous result (where form factors of the scattered proton were not studied). [ABSTRACT FROM AUTHOR]

In the tensor network representation, a deformed Z2 topological ground state wave function is proposed and its norm can be exactly mapped to the two-dimensional solvable Ashkin-Teller model. Then the topological (toric code) phase with anyonic excitations corresponds to the partial order phase of the Ashkin-Teller model, and possible topological phase transitions are precisely determined. With the electric-magnetic self-duality, a novel gapless Coulomb state with quasi-long-range order is obtained via a quantum Kosterlitz-Thouless phase transition. The corresponding ground state is a condensate of pairs of logarithmically confined electric charges and magnetic fluxes, and the scaling behavior of various anyon correlations can be exactly derived, revealing the effective interaction between anyons and their condensation. Deformations away from the self-duality drive the Coulomb state into either the gapped Higgs phase or the confining phase. [ABSTRACT FROM AUTHOR]

The bremsstrahlung of photons emitted during the scattering of p+ mesons off nuclei is studied for the first time. The role of interactions between p+ mesons and nuclei in the formation of the bremsstrahlung emission is analyzed in detail. We discover an essential contribution of photons emitted from nuclear part of the Johnson-Satchler potential to the full spectrum, in contrast with the optical Woods-Saxon potential. We observe an unusual essential influence of the nuclear part of both potentials on the spectrum at high photon energies. This phenomenon opens a new experimental way to study and check non-Coulomb and nuclear interactions between pions and nuclei via measurements of the emitted photons. We provide predictions of the bremsstrahlung spectra for pion scattering off 44Ca. [ABSTRACT FROM AUTHOR]

In the Fock representation, we construct matrix product states (MPS) for one-dimensional gapped phases for Zp parafermions. From the analysis of irreducibility of MPS, we classify all possible gapped phases of Zp parafermions without extra symmetry other than Zp charge symmetry, including topological phases, spontaneous symmetry breaking phases, and a trivial phase. For all phases, we find the irreducible forms of local matrices of MPS, which span different kinds of graded algebras. The topological phases are characterized by the nontrivial simple Zp graded algebras with the characteristic graded centers, yielding the degeneracies of the full transfer matrix spectra uniquely. However, the spontaneous symmetry breaking phases correspond to the trivial semisimple Zp / n graded algebras, which can be further reduced to the trivial simple Zp / n graded algebras, where n is the divisor of p . So the present results provide the complete classification of the parafermionic gapped phases and deepen our understanding of topological phases in one dimension. [ABSTRACT FROM AUTHOR]

The photoinduced martensitic (MT) transition and reverse transition in a shape memory alloy Mn50Ni40Sn10 have been examined by using high spatiotemporal resolution four-dimensional transmission electron microscopy (4D-TEM), and the experimental results clearly demonstrate that the MT transition and reverse transition in this Heusler alloy contain a variety of structural dynamic features at picosecond time scales. The 4D-TEM imaging and diffraction observations clearly show that MT transition and MT domain nucleation, which are related to cooperative atomic motions, occur at between 10 and 20 ps, depending on the thickness of the sample. Moreover, a strong coupling between the MT transition and lattice breathing mode is discovered in this system, which can result in a periodic structural oscillation between the MT phase and austenitic (AUS) phase. This allows us to directly observe the MT nucleation and domain wall motions in transient states using high spatiotemporal imaging. A careful analysis of the ultrafast images demonstrates the presence of remarkable transient states, which exhibit the essential features of MT nucleation, lattice symmetry breaking, and a rapid growth of MT plates. These results not only provide insights into the time-resolved structural dynamics and elementary mechanisms that govern the MT transition but also contribute to the development of a novel technique for future 4D-TEM investigations. [ABSTRACT FROM AUTHOR]

We generalize the theory of nuclear decay and capture of Gamow that is based on tunneling through the barrier and internal oscillations inside the nucleus. In our formalism an additional factor is obtained, which describes distribution of the wave function of the the α particle inside the nuclear region. We discover new most stable states (called quasibound states) of the compound nucleus (CN) formed during the capture of α particle by the nucleus. With a simple example, we explain why these states cannot appear in traditional calculations of the α capture cross sections based on monotonic penetrabilities of a barrier, but they appear in a complete description of the evolution of the CN. Our result is obtained by a complete description of the CN evolution, which has the advantages of (1) a clear picture of the formation of the CN and its disintegration, (2) a detailed quantum description of the CN, (3) tests of the calculated amplitudes based on quantum mechanics (not realized in other approaches), and (4) high accuracy of calculations (not achieved in other approaches). These peculiarities are shown with the capture reaction of α+44Ca. We predict quasibound energy levels and determine fusion probabilities for this reaction. The difference between our approach and theory of quasistationary states with complex energies applied for the α capture is also discussed. We show (1) that theory does not provide calculations for the cross section of α capture (according to modern models of the α capture), in contrast with our formalism, and (2) these two approaches describe different states of the α capture (for the same α-nucleus potential). [ABSTRACT FROM AUTHOR]

We study a frequency-dependent damping model of hyperdiffusion within the generalized Langevin equation. The model allows for the colored noise defined by its spectral density, assumed to be proportional to ωδ-1 at low frequencies with 0<δ<1 (sub-Ohmic damping) or 1<δ<2 (super-Ohmic damping), where the frequency-dependent damping is deduced from the noise by means of the fluctuation-dissipation theorem. It is shown that for super-Ohmic damping and certain parameters, the diffusive process of the particle in a titled periodic potential undergos sequentially four time regimes: thermalization, hyperdiffusion, collapse, and asymptotical restoration. For analyzing transition phenomenon of multidiffusive states, we demonstrate that the first exist time of the particle escaping from the locked state into the running state abides by an exponential distribution. The concept of an equivalent velocity trap is introduced in the present model; moreover, reformation of ballistic diffusive system is also considered as a marginal situation but does not exhibit the collapsed state of diffusion. [ABSTRACT FROM AUTHOR]

In transition metal oxide systems, there exists a serious discrepancy between the theoretical quasiparticle energies and the experimental photoemission energies. To improve the accuracy of electronic structure calculations for these systems, we use the all-electron mixed basis GW method, in which single-particle wave functions are accurately described by the linear combinations of plane waves and atomic orbitals. We adopt the full ω integration to evaluate the correlation part of the self-energy and compare the results with those obtained by plasmon pole models. We present the quasiparticle energies and band gap of titanium dioxide (TiO2) and zinc oxide (ZnO) within the one-shot GW approximation. The results are in reasonable agreement with experimental data in the case of TiO2 but underestimated by about 0.6-1.4 eV from experimental data in the case of ZnO, although our results are comparable to previous one-shot GW calculations. We also explain a new approach to perform ω integration very efficiently and accurately. [ABSTRACT FROM AUTHOR]

Applying a symmetric bulk bipartition to the one-dimensional Affleck-Kennedy-Lieb-Tasaki valence-bond solid (VBS) states for the integer spin-S Haldane gapped phase, we can create an array of fractionalized spin-S/2 edge states with the super unit cell l in the reduced bulk system, and the topological properties encoded in the VBS wave functions can be revealed. The entanglement Hamiltonian (EH) with even l corresponds to the quantum antiferromagnetic Heisenberg spin-S/2 model. For the even integer spins, the EH still describes the Haldane gapped phase. For the odd integer spins, however, the EH just corresponds to the quantum antiferromagnetic Heisenberg half-odd integer-spin model with spinon excitations, characterizing the critical point separating the topological Haldane phase from the trivial gapped phase. Our results thus demonstrate that the topological bulk property not only determines its fractionalized edge states but also the quantum criticality associated with the topological phase, where the elementary excitations are precisely those fractionalized edge degrees of freedom confined in the bulk of the topological phase. [ABSTRACT FROM AUTHOR]

The all-electron mixed basis GW approach is applied to calculate the electronic structure of rutile TiO2 and Ti0.75Nb0.25O2. The quasiparticle energies are calculated in fine detail, allowing the accurate determination of electronic structures. Although the valence band maximum (VBM) of the pure rutile TiO2 is composed of O 2p and Ti 3d orbitals, that of Ti0.75Nb0.25O2 is composed of Nb 4d orbitals and O 2p orbitals together with a few Ti 3d orbitals, forming an occupied impurity level, while the conduction band minimum is composed of Nb 4d and O 2p orbitals. In the calculation of Ti0.75Nb0.25O2, the energy level of the VBM increases, with finite energy gap, in contrast to the local density approximation calculation showing a metallic band structure. The exchange and correlation contributions to the self-energy drastically change in the VBM. The resulting electronic structure is in reasonable agreement with experiments. Based on our results, the GW approximation seems good in describing a not so strongly correlated transition metal oxide system with impurities. [ABSTRACT FROM AUTHOR]

The critical theories for the topological phase transitions of integer quantum Hall states to a trivial insulating state with the same symmetry can be obtained by calculating the ground state entanglement spectrum under a symmetric checkerboard bipartition. In contrast to the gapless edge excitations under the left-right bipartition, a quantum network with bulk gapless excitations naturally emerges at the Brillouin zone center without fine tuning. On a large finite lattice, the resulting critical theory for the v =1 state is the (2+1) dimensional relativistic quantum field theory characterized by a single Dirac cone spectrum and a pair of fractionalized zero-energy states, while for the v =2 state the critical theory exhibits a parabolic spectrum and no sign of fractionalization in the zero-energy states. A triangular correspondence is established among the bulk topological theory, gapless edge theory, and the critical theory via the ground state entanglement spectrum. [ABSTRACT FROM AUTHOR]

Under an appropriate symmetric extensive bipartition in a one-dimensional symmetry-protected topological (SPT) phase, a bulk critical-entanglement spectrum can be obtained, resembling the excitation spectrum of the critical point separating the SPT phase from the trivial (vacuum) state. Such a critical point is beyond the standard Landau-Ginzburg-Wilson paradigm for symmetry-breaking phase transitions. For the S = 1 SPT (Haldane) phase with the Affleck-Kennedy-Lieb-Tasaki exact wave function, the resulting critical-entanglement spectrum has a residual entropy per lattice site sr = 0.67602, showing a delocalized version of the edge excitations in the SPT phase. From the wave function corresponding to the lowest entanglement energy level, the central charge of the critical point can be extracted c ≈ 1.01 ± 0.01. The critical theory can be identified as the same effective field theory as the spin-1/2 antiferromagnetic Heisenberg chain or the spin-1/2 Haldane-Shastry model with inverse-square long-range interaction. [ABSTRACT FROM AUTHOR]

The possible heavy fermion superconductivity is carefully reexamined in the two-dimensional Kondo lattice model with an antiferromagnetic Heisenberg superexchange between local magnetic moments. To establish an effective mean field theory in the limit of paramagnetic heavy Fermi liquid and near the half-filling case, we find that the spinon singlet pairing from the local antiferromagnetic short-range correlations can reduce the ground state energy substantially. In the presence of the Kondo screening effect, the Cooper pairs between the conduction electrons are induced. Depending on the ratio of the Heisenberg and the Kondo exchange couplings, the resulting superconducting state is characterized by either a d-wave nodal or d-wave nodeless state, and a continuous phase transition exists between these two states. These results are related to some quasi-two-dimensional heavy fermion superconductors. [ABSTRACT FROM AUTHOR]

A crucial subroutine in quantum computing is to load the classical data of N complex numbers into the amplitude of a superposed n=⌈log_{2}N⌉-qubit state. It has been proven that any algorithm universally implementing this subroutine would need at least O(N) constant weight operations. However, the proof assumes that only n qubits are used, whereas the circuit depth could be reduced by extending the space and allowing ancillary qubits. Here we investigate this space-time tradeoff in quantum state preparation with classical data. We propose quantum algorithms with O(n^{2}) circuit depth to encode any N complex numbers using only single- and two-qubit gates, and local measurements with ancillary qubits. Different variances of the algorithm are proposed with different space and runtime. In particular, we present a scheme with O(N^{2}) ancillary qubits, O(n^{2}) circuit depth, and O(n^{2}) average runtime, which exponentially improves the conventional bound. While the algorithm requires more ancillary qubits, it consists of quantum circuit blocks that only simultaneously act on a constant number of qubits, and at most O(n) qubits are entangled. We also prove a fundamental lower bound Ω(n) for the minimum circuit depth and runtime with an arbitrary number of ancillary qubits, aligning with our scheme with O(n^{2}). The algorithms are expected to have wide applications in both near-term and universal quantum computing.

The non-Abelian topological phase with Fibonacci anyons minimally supports universal quantum computation. In order to investigate the possible phase transitions out of the Fibonacci topological phase, we propose a generic quantum-net wave function with two tuning parameters dual with each other, and the norm of the wave function can be exactly mapped into a partition function of the two-coupled ϕ²-state Potts models, where ϕ=(√5+1)/2 is the golden ratio. By developing the tensor network representation of this wave function on a square lattice, we can accurately calculate the full phase diagram with the numerical methods of tensor networks. More importantly, it is found that the non-Abelian Fibonacci topological phase is enclosed by three distinct nontopological phases and their dual phases of a single ϕ²-state Potts model: the gapped dilute net phase, critical dense net phase, and spontaneous translation symmetry breaking gapped phase. We also determine the critical properties of the phase transitions among the Fibonacci topological phase and those nontopological phases. [ABSTRACT FROM AUTHOR]

We investigate possibility of emission of bremsstrahlung photons in nuclear reactions with hypernuclei for the first time. A new model of bremsstrahlung emission which accompanies interactions between α particles and hypernuclei is constructed, where a new formalism for magnetic moments of nucleons and a hyperon inside a hypernucleus is added. To start calculations, we choose α decay of normal nucleus 210Po and hypernucleus 211ΛPo. We find that (1) emission for the hypernucleus 211ΛPo is larger than for the normal nucleus 210Po and (2) the difference between these spectra is small. We propose a way to find the hypernuclei where the role of hyperon is the most essential in emission of the bremsstrahlung photons during α decay. As demonstration of such a property, we show that spectra for the hypernuclei 107ΛTe and 109ΛTe are essentially larger than the spectra for the normal nuclei 106Te and 108Te. Such a difference is explained by additional contribution of emission to the full bremsstrahlung, which is formed by magnetic moment of hyperon inside hypernucleus. The bremsstrahlung emission formed by such a mechanism is of magnetic type. A new formula for fast estimations of bremsstrahlung spectra for even-even hypernuclei is proposed, where the role of the magnetic moment of the hyperon of the hypernucleus in formation of bremsstrahlung emission is shown explicitly. Then we applied our model to study bremsstrahlung emission in α decay of light hypernuclei 10ΛBe10 and 10ΛB (which was the subject of investigations at the Nuclotron at JINR, Dubna). Such an analysis opens the possibility of new experimental study of properties of the hypernuclei via bremsstrahlung study. [ABSTRACT FROM AUTHOR]

To understand the recently observed high temperature superconductivity in the monolayer CuO2 grown on the Bi2Sr2CaCu2O8+δ substrates, we propose a two-band model of the hybridized oxygen px and py orbitals with the proximity effect of the substrate. We demonstrate that both the nodal and nodeless superconducting states can be induced by the proximity effect, depending on the strengths of the pairing parameters. [ABSTRACT FROM AUTHOR]

Different from the spin-1 Haldane gapped phase, we propose an SO(3) spin-1 matrix product state (MPS), whose parent Hamiltonian includes three-site spin interactions. From the entanglement spectrum of a single block with l sites, an enlarged SU(3) symmetry is identified in the edge states, which are conjugate to each other for the l=even block but identical for the l=odd block. By blocking this state, the blocked MPS explicitly displays the SU(3) symmetry with two distinct structures. Under a symmetric bulk bipartition with a sufficient large block length l=even, the entanglement Hamiltonian (EH) of the reduced system characterizes a spontaneous dimerized phase with twofold degeneracy. However, for the block length l=odd, the corresponding EH represents an SU(3) quantum critical point with delocalized edge quasiparticles, and the critical field theory is described by the SU(3) level-1 Wess-Zumino-Witten conformal field theory. [ABSTRACT FROM AUTHOR]

A common feature of topological phases of matter is the fractionalization of the quantum number in their low-energy excitations. Such information is encoded in their ground state wave functions, but emerges in the bipartite entanglement spectra. The symmetric extensive bipartition is an effective novel method to create deconfined fractionalized edge particles in the reduced subsystem, which lead to quantum critical behavior associated with the transition from the topological phase to its adjacent trivial phase. Here we report the interesting results revealed by applying this method to the one-dimensional SO(5) symmetric valence-bond solid state being a spin-2 symmetry protected topological phase. From the finite-size entanglement spectrum, we find the lowest level to be an SO(5) singlet with a logarithmic entanglement entropy. Surprisingly, the first excited level is also an SO(5) singlet and the spectral gap scales with the subsystem size as LA-ν with ν≃1.978. In the thermodynamic limit, a novel quantum criticality emerges with SO(5) spinons and their four-body singlet bound states as elementary excitations, hence ruling out the possibility of being described by a conformal field theory. Moreover, the entanglement Hamiltonian can be determined as an SO(5) symmetric nearest neighbor spin-3/2 quadruple-quadruple interaction with a negative coupling. Our work thus demonstrates the power of this new method in the study of quantum criticality encoded in the topological ground states. [ABSTRACT FROM AUTHOR]

We demonstrate an efficient experimental scheme for producing polarization-entangled photon pairs from spontaneous four-wave mixing (SFWM) in a laser-cooled 85Rb atomic ensemble, with a bandwidth (as low as 0.8 MHz) much narrower than the rubidium atomic natural linewidth. By stabihzing the relative phase between the two SFWM paths in a Mach-Zehnder interferometer configuration, we are able to produce all four Bell states. These subnatural-linewidth photon pairs with polarization entanglement are ideal quantum information carriers for connecting remote atomic quantum nodes via efficient light-matter interaction in a photon-atom quantum network. [ABSTRACT FROM AUTHOR]

We use scanning tunneling microscopy to investigate the (001) surface of a cleaved SmB6 Kondo insulator. Variable temperature dI/dV spectroscopy up to 60 K reveals a gaplike density of state suppression around the Fermi level, which is due to the hybridization between the itinerant Sm 5d band and localized Sm 4f band. At temperatures below 40 K, a sharp coherence peak emerges within the hybridization gap near the lower gap edge. We propose that the in-gap resonance state is due to a collective excitation in magnetic origin with the presence of spin-orbital coupling and mixed valence fluctuations. These results shed new light on the electronic structure evolution and transport anomaly in SmB6. [ABSTRACT FROM AUTHOR]