The properties of a bound polaron in a parabolic quantum dot with weak electron-LO-phonon coupling under a Coulomb field are studied. The ground state energy of the bound polaron is derived by using a linear combinati...The properties of a bound polaron in a parabolic quantum dot with weak electron-LO-phonon coupling under a Coulomb field are studied. The ground state energy of the bound polaron is derived by using a linear combination operator and the perturbation method. The influence of the interaction between phonons with different wave vectors in the recoil process on the ground state energy of the bound polaron is discussed. Numerical calculations are performed,and the results show that the ground state energy increases significantly as the effective confinement length of the quantum dot decreases,considering of the interaction between phonons. When l0〉1.0, the influence of the interaction between phonons on the ground state energy cannot be ignored.展开更多
In a recent measurement LHCb reported pronounced structures in the J/ψJ/ψspectrum.One of the various possible explanations of those is that they emerge from non-perturbative interactions of vector charmonia.It is th...In a recent measurement LHCb reported pronounced structures in the J/ψJ/ψspectrum.One of the various possible explanations of those is that they emerge from non-perturbative interactions of vector charmonia.It is thus important to understand whether it is possible to form a bound state of two charmonia interacting through the exchange of gluons,which hadronise into two pions at the longest distance.In this paper,we demonstrate that,given our current understanding of hadron-hadron interactions,the exchange of correlated light mesons(pions and kaons)is able to provide sizeable attraction to the di-J/ψsystem,and it is possible for two J/ψmesons to form a bound state.As a side result we find from an analysis of the data for theψ/(2 S)J/ψππtransition including bothππand KK final state interactions an improved value for theψ(2 S)→J/ψtransition chromo-electric polarisability:|αψ(2 S)J/ψ|=(1.8±0.1)GeV-3,where the uncertainty also includes the one induced by the final state interactions.展开更多
We determine explicitly the exact transcendental bound states energies equation for a one-dimensional harmonic oscillator perturbed by a single and a double point interactions via Green's function techniques using...We determine explicitly the exact transcendental bound states energies equation for a one-dimensional harmonic oscillator perturbed by a single and a double point interactions via Green's function techniques using both momentum and position space representations. The even and odd solutions of the problem are discussed. The corresponding limiting cases are recovered. For the harmonic oscillator with a point interaction in more than one dimension,divergent series appear. We use to remove this divergence an exponential regulator and we obtain a transcendental equation for the energy bound states. The results obtained here are consistent with other investigations using different methods.展开更多
The conductance spectra of a graphene ribbon and graphene-superconductor （G-S） junctions are investi- gated, using the tight-binding model and non-equilibrium Green＇s function formalism. It is found that the quanti...The conductance spectra of a graphene ribbon and graphene-superconductor （G-S） junctions are investi- gated, using the tight-binding model and non-equilibrium Green＇s function formalism. It is found that the quantized conductance related to graphene＇s edge-states is robust against perturbations in the model parameters for a graphene monolayer ribbon with the zigzag boundary. With appropriate a new bound state with odd-frequency symmetry is found in conductance amplitude is followed model parameter of the spin-orbit interaction strength, the G-S junction. An enhancement in the zero-energy展开更多
In this paper, we investigate topological phases of a-graphyne with tight-binding method. By calculating the topological invariant Z2 and the edge states, we identify topological insulators. We present the phase diagr...In this paper, we investigate topological phases of a-graphyne with tight-binding method. By calculating the topological invariant Z2 and the edge states, we identify topological insulators. We present the phase diagrams of a-graphyne with different filling fractions as a function of spin-orbit interaction and the nearest-neighbor hopping energy. We find there exist topological insulators in a-graphyne. We analyze and discuss the characteristics of topological phases of a-graphyne.展开更多
We study the underlying symmetry in a spin-orbit coupled tight-binding model with Hubbard interaction.It is shown that,in the absence of the on-site interaction,the system possesses the SU(2)symmetry arising from the ...We study the underlying symmetry in a spin-orbit coupled tight-binding model with Hubbard interaction.It is shown that,in the absence of the on-site interaction,the system possesses the SU(2)symmetry arising from the time reversal symmetry.The influence of the on-site interaction on the symmetry depends on the topology of the networks:The SU(2)symmetry is shown to be the spin rotation symmetry of a simply-connected lattice even in the presence of the Hubbard interaction.On the contrary,the on-site interaction breaks the SU(2)symmetry of a multi-connected lattice.This fact indicates that a discrete spin-orbit coupled system has exclusive features from its counterpart in a continuous system.The obtained rigorous result is illustrated by a simple ring system.展开更多
文摘The properties of a bound polaron in a parabolic quantum dot with weak electron-LO-phonon coupling under a Coulomb field are studied. The ground state energy of the bound polaron is derived by using a linear combination operator and the perturbation method. The influence of the interaction between phonons with different wave vectors in the recoil process on the ground state energy of the bound polaron is discussed. Numerical calculations are performed,and the results show that the ground state energy increases significantly as the effective confinement length of the quantum dot decreases,considering of the interaction between phonons. When l0〉1.0, the influence of the interaction between phonons on the ground state energy cannot be ignored.
基金supported in part by the Chinese Academy of Sciences(CAS)under Grants No.XDPB15,No.XDB34030000,and No.QYZDB-SSW-SYS013the National Natural Science Foundation of China(NSFC)under Grants No.11835015,No.12047503 and No.11961141012+1 种基金the NSFC and the Deutsche Forschungsgemeinschaft(DFG)through the funds provided to the Sino-German Collaborative Research Center‘‘Symmetries and the Emergence of Structure in QCD”(NSFC Grant No.12070131001,DFG Project-ID 196253076–TRR110)supported by Ministry of Science and Education of Russian Federation under Grant 14.W03.31.0026。
文摘In a recent measurement LHCb reported pronounced structures in the J/ψJ/ψspectrum.One of the various possible explanations of those is that they emerge from non-perturbative interactions of vector charmonia.It is thus important to understand whether it is possible to form a bound state of two charmonia interacting through the exchange of gluons,which hadronise into two pions at the longest distance.In this paper,we demonstrate that,given our current understanding of hadron-hadron interactions,the exchange of correlated light mesons(pions and kaons)is able to provide sizeable attraction to the di-J/ψsystem,and it is possible for two J/ψmesons to form a bound state.As a side result we find from an analysis of the data for theψ/(2 S)J/ψππtransition including bothππand KK final state interactions an improved value for theψ(2 S)→J/ψtransition chromo-electric polarisability:|αψ(2 S)J/ψ|=(1.8±0.1)GeV-3,where the uncertainty also includes the one induced by the final state interactions.
基金Supported by the Algerian Ministry of Higher Education and Scientific Research under the CNEPRU project No.D01720140001
文摘We determine explicitly the exact transcendental bound states energies equation for a one-dimensional harmonic oscillator perturbed by a single and a double point interactions via Green's function techniques using both momentum and position space representations. The even and odd solutions of the problem are discussed. The corresponding limiting cases are recovered. For the harmonic oscillator with a point interaction in more than one dimension,divergent series appear. We use to remove this divergence an exponential regulator and we obtain a transcendental equation for the energy bound states. The results obtained here are consistent with other investigations using different methods.
基金Supported by the National Natural Science Foundation of China under Grant No.61271163
文摘The conductance spectra of a graphene ribbon and graphene-superconductor （G-S） junctions are investi- gated, using the tight-binding model and non-equilibrium Green＇s function formalism. It is found that the quantized conductance related to graphene＇s edge-states is robust against perturbations in the model parameters for a graphene monolayer ribbon with the zigzag boundary. With appropriate a new bound state with odd-frequency symmetry is found in conductance amplitude is followed model parameter of the spin-orbit interaction strength, the G-S junction. An enhancement in the zero-energy
基金Supported by the National Natural Science Foundation of China under Grant Nos.11004028 and 11274061
文摘In this paper, we investigate topological phases of a-graphyne with tight-binding method. By calculating the topological invariant Z2 and the edge states, we identify topological insulators. We present the phase diagrams of a-graphyne with different filling fractions as a function of spin-orbit interaction and the nearest-neighbor hopping energy. We find there exist topological insulators in a-graphyne. We analyze and discuss the characteristics of topological phases of a-graphyne.
基金supported by the National Natural Science Foundation of China(Grant No.11374163)the National Basic Research Program of China(Grant No.2012CB921900)
文摘We study the underlying symmetry in a spin-orbit coupled tight-binding model with Hubbard interaction.It is shown that,in the absence of the on-site interaction,the system possesses the SU(2)symmetry arising from the time reversal symmetry.The influence of the on-site interaction on the symmetry depends on the topology of the networks:The SU(2)symmetry is shown to be the spin rotation symmetry of a simply-connected lattice even in the presence of the Hubbard interaction.On the contrary,the on-site interaction breaks the SU(2)symmetry of a multi-connected lattice.This fact indicates that a discrete spin-orbit coupled system has exclusive features from its counterpart in a continuous system.The obtained rigorous result is illustrated by a simple ring system.
