The(2+1)-dimensional elliptic Toda equation is a high-dimensional generalization of the Toda lattice and a semidiscrete Kadomtsev–Petviashvili I equation.This paper focuses on investigating the resonant interactions ...The(2+1)-dimensional elliptic Toda equation is a high-dimensional generalization of the Toda lattice and a semidiscrete Kadomtsev–Petviashvili I equation.This paper focuses on investigating the resonant interactions between two breathers,a breather/lump and line solitons as well as lump molecules for the(2+1)-dimensional elliptic Toda equation.Based on the N-soliton solution,we obtain the hybrid solutions consisting of line solitons,breathers and lumps.Through the asymptotic analysis of these hybrid solutions,we derive the phase shifts of the breather,lump and line solitons before and after the interaction between a breather/lump and line solitons.By making the phase shifts infinite,we obtain the resonant solution of two breathers and the resonant solutions of a breather/lump and line solitons.Through the asymptotic analysis of these resonant solutions,we demonstrate that the resonant interactions exhibit the fusion,fission,time-localized breather and rogue lump phenomena.Utilizing the velocity resonance method,we obtain lump–soliton,lump–breather,lump–soliton–breather and lump–breather–breather molecules.The above works have not been reported in the(2+1)-dimensional discrete nonlinear wave equations.展开更多
In this paper, we study the nonclassical properties of the electromagnetic field resulting from the interaction of a three-level ∧-type atom with a two-mode field initially in the coherent state, such as squeezing pr...In this paper, we study the nonclassical properties of the electromagnetic field resulting from the interaction of a three-level ∧-type atom with a two-mode field initially in the coherent state, such as squeezing properties and sub-Poisson statistics. We show that the squeezing can be enhanced by selective atomic measurement.展开更多
In this paper, a scheme for generating various multiatom entangled graph states via resonant interactions is proposed. We investigate the generation of various four-atom graph states first in the ideal case and then i...In this paper, a scheme for generating various multiatom entangled graph states via resonant interactions is proposed. We investigate the generation of various four-atom graph states first in the ideal case and then in the case in which the cavity decay and atomic spontaneous emission are taken into consideration in the process of interaction. More importantly, we improve the possible distortion of the graph states coming from cavity decay and atomic spontaneous emission by performing appropriate unitary transforms on atoms. The generation of multiatom entangled graph states is very important for constructing quantum one-way computer in a fault-tolerant manner. The resonant interaction time is very short, which is important in the sense of decoherence. Our scheme is easy and feasible within the reach of current experimental technology.展开更多
This paper proposes a scheme for the generation of entangled coherent states for two cavity modes. In the scheme a V-type three-level atom is sent through a two-mode cavity filled with a coherent field. After the atom...This paper proposes a scheme for the generation of entangled coherent states for two cavity modes. In the scheme a V-type three-level atom is sent through a two-mode cavity filled with a coherent field. After the atom cavity interaction and detection of the atomic state the cavity modes may evolve to a superposition of two-mode coherent states. As the scheme is based on resonant atom-cavity interaction, the required interaction time is short, which is important in view of the decoherence. Moreover, additional classical pulses are unnecessary before and after the atom-cavlty interaction.展开更多
The basic equations of free capillary_gravity surface_waves in a circular cylindrical basin were derived from Luke's principle. Taking Galerkin's expansion of the velocity potential and the free surface elevat...The basic equations of free capillary_gravity surface_waves in a circular cylindrical basin were derived from Luke's principle. Taking Galerkin's expansion of the velocity potential and the free surface elevation, the second_order perturbation equations were derived by use of expansion of multiple scale. The nonlinear interactions with the second order internal resonance of three free surface_waves were discussed based on the above. The results include:derivation of the couple equations of resonant interactions among three waves and the conservation laws; analysis of the positions of equilibrium points in phase plane; study of the resonant parameters and the non_resonant parameters respectively in all kinds of circumstances; derivation of the stationary solutions of the second_order interaction equations corresponding to different parameters and analysis of the stability property of the solutions; discussion of the effective solutions only in the limited time range. The analysis makes it clear that the energy transformation mode among three waves differs because of the different initial conditions under nontrivial circumstance. The energy may either exchange among three waves periodically or damp or increase in single waves.展开更多
We propose a scheme to implement the n-qubit Deutsch-Jozsa algorithm based on resonant interaction between the atoms and a single-mode cavity. In the scheme, the resonant transitions between two ground states and one ...We propose a scheme to implement the n-qubit Deutsch-Jozsa algorithm based on resonant interaction between the atoms and a single-mode cavity. In the scheme, the resonant transitions between two ground states and one excited state of an atom are changed alternately by adjusting the cavity frequency appropriately, and the operations required to complete the algorithm can be significantly simplified following the increment of the number of qubits. The implementation of the scheme in experiment would show the full power of quantum algorithm and would be significative and important for more complicated quantum algorithm in cavity quantum electrodynamics.展开更多
In this paper we propose a scheme in which two-mode entanglement in a steady state is produced by using two lasers to resonantly drive a single four-level atom embedded inside a two-mode optical cavity. In this scheme...In this paper we propose a scheme in which two-mode entanglement in a steady state is produced by using two lasers to resonantly drive a single four-level atom embedded inside a two-mode optical cavity. In this scheme, atomic coherence induced by a classical laser plays an important role in the process of preparing the entangled state. With the coupling of a strong control field, direct two-photon transition is generated and the relatively weak pump field induces the parametric interaction between two photons, which makes them entangle with each other. By numerical calculation, we find that the degree of entanglement depends strongly on the Rabi frequencies of the classical laser fields and the cavity losses.展开更多
This paper proposes a scheme for generating arbitrary superpositions of several coherent states along a straight line for a cavity mode. In the scheme, several atoms are sent through a cavity initially in a strong coh...This paper proposes a scheme for generating arbitrary superpositions of several coherent states along a straight line for a cavity mode. In the scheme, several atoms are sent through a cavity initially in a strong coherent state. The superposition of several coherent states with desired coefficients may be generated if each atom is detected in the excited state after it exits the cavity. The scheme is based on resonant atom-cavity interaction and no classical field is required during and after the atom cavity interaction. Thus, the scheme is very simple and the interaction time is very short, which is important in view of decoherence.展开更多
We use the photon Green-function method to study the quantum resonant dipole-dipole interaction(RDDI) induced by an Ag nanosphere(ANP).As the distance between the two dipoles increases,the RDDI becomes weaker,whic...We use the photon Green-function method to study the quantum resonant dipole-dipole interaction(RDDI) induced by an Ag nanosphere(ANP).As the distance between the two dipoles increases,the RDDI becomes weaker,which is accompanied by the influence of the higher-order mode of the ANP on RDDI declining more quickly than that of the dipole mode.Across a broad frequency range(above 0.05 eV),the transfer rate of the RDDI is nearly constant since the two dipoles are fixed at the proper position.In addition,this phenomenon still exists for slightly different radius of the ANPs.We find that the frequency corresponding to the maximum transfer rate of RDDI exhibits a monotonic decrease by moving away one dipole as the other dipole and the ANP are kept fixed.In addition,the radius of ANP has little effect on this.When the two dipoles are far from the ANP,the maximum transfer rate of the RDDI takes place at the frequency of the dipole mode.In contrast,when the two dipoles are close to the ANP,the higher-order modes come into effect and they will play a leading role in the RDDI if they match the transition frequency of the dipole.Our results may be used in a biological detector and have a certain guiding significance for further application.展开更多
A scheme for implementing a two-qubit phase gate with atoms sent through a high-Q optical cavity is proposed by choosing nonidentical coupling constants between the atoms and cavity. The atomic spontaneous emission ca...A scheme for implementing a two-qubit phase gate with atoms sent through a high-Q optical cavity is proposed by choosing nonidentical coupling constants between the atoms and cavity. The atomic spontaneous emission can be suppressed due to the large atom-field detuning. Moreover, the scheme can be generalized to implement an N-qubit phase gate and the gating time does not change with an increase of the number of qubits.展开更多
A scheme is proposed for generating entangled W states with four cavity modes. In this scheme, we send a V-type three-level atom through two identical two-mode cavities in succession. After the atom exits from the sec...A scheme is proposed for generating entangled W states with four cavity modes. In this scheme, we send a V-type three-level atom through two identical two-mode cavities in succession. After the atom exits from the second cavity, the four cavity modes are prepared in the W state. On the other hand we can obtain three-atom W states by sending three V-type three-level atoms through a two-mode cavity in turn. The present scheme does not require conditional measurement, and it is easily generalized to preparing 2n-mode W states and n-atom W states.展开更多
The existence of specific biorhythms and the role of geomagnetic and/or solar magnetic activities are well-established by appropriate correlations in chronobiology. From a physical viewpoint, there are two different a...The existence of specific biorhythms and the role of geomagnetic and/or solar magnetic activities are well-established by appropriate correlations in chronobiology. From a physical viewpoint, there are two different accesses to biorhythms to set up connections to molecular processes: quantum mechanical perturbation theoretical methods and their resonance dominators to characterize specific interactions between constituents. These methods permit the treatment of molecular processes by circuits with characteristic resonances and “beat-frequencies”, which result from primarily fast physical processes. As examples, the tunneling processes between DNA base pairs (H bonds), the ATP decomposition and the irradiation of tumor cells are accounted for.展开更多
This paper proposes an alternative scheme for generating four-photon W state via cavity QED. The scheme bases on the resonant interaction of a A-type three level atom with two bimodal cavities. The detection of atom c...This paper proposes an alternative scheme for generating four-photon W state via cavity QED. The scheme bases on the resonant interaction of a A-type three level atom with two bimodal cavities. The detection of atom collapses the cavity to the desired state. Comparing with previous schemes, the advantage of this scheme is that the interaction time can be greatly shortened since it uses the resonant interaction between atom and cavities. Moreover, the proposed scheme is more experimentally feasible than the previous ones.展开更多
This paper proposes a scheme for the implementation of 1→ 3 optimal phase-covariant quantum cloning with trapped ions. In the present protocol, the required time for the whole procedure is short due to the resonant i...This paper proposes a scheme for the implementation of 1→ 3 optimal phase-covariant quantum cloning with trapped ions. In the present protocol, the required time for the whole procedure is short due to the resonant interaction, which is important in view of decoherence. Furthermore, the scheme is feasible based on current technologies.展开更多
Free surface waves in a cylinder of liquid under vertical excitation with slowly modulated amplitude are investigated in the current paper. It is shown by both theoretical analysis and numerical simulation that chaos ...Free surface waves in a cylinder of liquid under vertical excitation with slowly modulated amplitude are investigated in the current paper. It is shown by both theoretical analysis and numerical simulation that chaos may occur even for a single mode with modulation which can be used to explain Gollub and Meyer's experiment. The implied resonant mechanism accounting for this phenomenon is further elucidated.展开更多
This paper proposes a decoherence-immune scheme for generating highly entangled states for two atoms trapped in a cavity. The scheme is based on two resonant atom-cavity interactions. Conditional upon the detection of...This paper proposes a decoherence-immune scheme for generating highly entangled states for two atoms trapped in a cavity. The scheme is based on two resonant atom-cavity interactions. Conditional upon the detection of no photon, the two atoms may exchange an excitation via the first resonant interaction, which leads to entanglement. Due to the loss of the excitation, the two atoms are in a mixed entangled state. With the help of an auxiliary ground state not coupled to the cavity mode, the state related to the excitation loss is eliminated by the detection of a photon resulting from the second resonant interaction. Thus, the fidelity of entanglement is almost not affected by the decoherence.展开更多
Near-diurnal vertically-standing waves with high vertical wavenumbers k z were observed in the velocity and shear fi elds from a set of 75-d long ADCP moored in the northeastern South China Sea(SCS)away from the“crit...Near-diurnal vertically-standing waves with high vertical wavenumbers k z were observed in the velocity and shear fi elds from a set of 75-d long ADCP moored in the northeastern South China Sea(SCS)away from the“critical”latitude of 28.8°.These enhanced near-diurnal internal waves followed a fortnightly spring-neap cycle.However,they always happened during semidiurnal spring tides rather than diurnal springs although strong diurnal internal tides with the fortnightly spring-neap cycle were prevailing,suggesting that they were generated via subharmonic instability(PSI)of dominant semidiurnal M 2 internal tides.When two semidiurnal internal tidal waves with opposite vertical propagation direction intersected,both semidiurnal subharmonic and super harmonic waves were largely intensifi ed.The observed maximum diurnal velocity amplitudes were up to 0.25 m/s.The kinetic energy and shear spectra further suggested that frequencies of daughter waves were not always perfectly equal to M 2/2.The superposition of two daughter waves with nearly equal frequencies and nearly opposite k z in a PSI-triad leaded to the vertically-standing waves.展开更多
This paper presents a method for generating entanglement molecules, which is introduced by Dur (2001 Phys. Rev. A). In this scheme, N ladder-type three-level atoms are sent through a resonant weak coherent cavity fi...This paper presents a method for generating entanglement molecules, which is introduced by Dur (2001 Phys. Rev. A). In this scheme, N ladder-type three-level atoms are sent through a resonant weak coherent cavity field, then the system states are measured. And the system field may collapse onto some possible types of entanglement molecules. Meanwhile it discusses about the interaction time from the experimental point of view, and compare the result with the previous scheme proposed by Huang (2004 J. Phys. B: At. Mol. Opt. Phys.).展开更多
The single photon scattering properties in a pair of waveguides coupled by a whispering-gallery resonator in- teracting with a semiconductor quantum dot are investigated theoretically. The two waveguides support four ...The single photon scattering properties in a pair of waveguides coupled by a whispering-gallery resonator in- teracting with a semiconductor quantum dot are investigated theoretically. The two waveguides support four possible ports for an incident single photon. The quantum dot is considered a V-type system. The incident direction-dependent single photon scattering properties are studied and equal-output probability from the four ports for a single photon incident is discussed. The influences of backscattering between the two modes of the whispering-gallery resonator for incident direction-dependent single photon scattering properties are also pre- sented.展开更多
Dipole Research EXperiment(DREX) is a new terrella device as part of the Space Plasma Environment Research Facility(SPERF) for laboratory studies of space physics relevant to the inner magnetospheric plasmas. Adeq...Dipole Research EXperiment(DREX) is a new terrella device as part of the Space Plasma Environment Research Facility(SPERF) for laboratory studies of space physics relevant to the inner magnetospheric plasmas. Adequate plasma sources are very important for DREX to achieve its scientific goals. According to different research requirements, there are two density regimes for DREX. The low density regime will be achieved by an electron cyclotron resonance(ECR) system for the ‘whistler/chorus' wave investigation, while the high density regime will be achieved by biased cold cathode discharge for the desired ‘Alfvén' wave study. The parameters of ‘whistler/chorus' waves and ‘Alfvén' waves are determined by the scaling law between space and laboratory plasmas in the current device. In this paper, the initial design of these two plasma sources for DREX is described. Focus is placed on the chosen frequency and operation mode of the ECR system which will produce relatively low density ‘artificial radiation belt' plasmas and the seed electrons, followed by the design of biased cold cathode discharge to generate plasma with high density.展开更多
基金the National Natural Science Foundation of China(Grant Nos.12061051 and 11965014)。
文摘The(2+1)-dimensional elliptic Toda equation is a high-dimensional generalization of the Toda lattice and a semidiscrete Kadomtsev–Petviashvili I equation.This paper focuses on investigating the resonant interactions between two breathers,a breather/lump and line solitons as well as lump molecules for the(2+1)-dimensional elliptic Toda equation.Based on the N-soliton solution,we obtain the hybrid solutions consisting of line solitons,breathers and lumps.Through the asymptotic analysis of these hybrid solutions,we derive the phase shifts of the breather,lump and line solitons before and after the interaction between a breather/lump and line solitons.By making the phase shifts infinite,we obtain the resonant solution of two breathers and the resonant solutions of a breather/lump and line solitons.Through the asymptotic analysis of these resonant solutions,we demonstrate that the resonant interactions exhibit the fusion,fission,time-localized breather and rogue lump phenomena.Utilizing the velocity resonance method,we obtain lump–soliton,lump–breather,lump–soliton–breather and lump–breather–breather molecules.The above works have not been reported in the(2+1)-dimensional discrete nonlinear wave equations.
文摘In this paper, we study the nonclassical properties of the electromagnetic field resulting from the interaction of a three-level ∧-type atom with a two-mode field initially in the coherent state, such as squeezing properties and sub-Poisson statistics. We show that the squeezing can be enhanced by selective atomic measurement.
基金Project supported by the National Natural Science Foundation of China (Grant Nos 60678022 and 10704001)the Specialized Research Fund for the Doctoral Program of Higher Education, China (Grant No 20060357008)+2 种基金Anhui Provincial Natural Science Foundation, China (Grant No 070412060)the Key Program of the Education Department of Anhui Province, China (Grant Nos KJ2008A28ZC, KJ2008B83ZC, KJ2008B265 and KJ2007B082)the Talent Foundation of Anhui University, China,and the Anhui Key Laboratory of Information Materials and Devices (Anhui University), China
文摘In this paper, a scheme for generating various multiatom entangled graph states via resonant interactions is proposed. We investigate the generation of various four-atom graph states first in the ideal case and then in the case in which the cavity decay and atomic spontaneous emission are taken into consideration in the process of interaction. More importantly, we improve the possible distortion of the graph states coming from cavity decay and atomic spontaneous emission by performing appropriate unitary transforms on atoms. The generation of multiatom entangled graph states is very important for constructing quantum one-way computer in a fault-tolerant manner. The resonant interaction time is very short, which is important in the sense of decoherence. Our scheme is easy and feasible within the reach of current experimental technology.
基金Project supported by the National Natural Science Foundation of China (Grant No 10674025)the Funds from Fuzhou University
文摘This paper proposes a scheme for the generation of entangled coherent states for two cavity modes. In the scheme a V-type three-level atom is sent through a two-mode cavity filled with a coherent field. After the atom cavity interaction and detection of the atomic state the cavity modes may evolve to a superposition of two-mode coherent states. As the scheme is based on resonant atom-cavity interaction, the required interaction time is short, which is important in view of the decoherence. Moreover, additional classical pulses are unnecessary before and after the atom-cavlty interaction.
文摘The basic equations of free capillary_gravity surface_waves in a circular cylindrical basin were derived from Luke's principle. Taking Galerkin's expansion of the velocity potential and the free surface elevation, the second_order perturbation equations were derived by use of expansion of multiple scale. The nonlinear interactions with the second order internal resonance of three free surface_waves were discussed based on the above. The results include:derivation of the couple equations of resonant interactions among three waves and the conservation laws; analysis of the positions of equilibrium points in phase plane; study of the resonant parameters and the non_resonant parameters respectively in all kinds of circumstances; derivation of the stationary solutions of the second_order interaction equations corresponding to different parameters and analysis of the stability property of the solutions; discussion of the effective solutions only in the limited time range. The analysis makes it clear that the energy transformation mode among three waves differs because of the different initial conditions under nontrivial circumstance. The energy may either exchange among three waves periodically or damp or increase in single waves.
基金Project supported by the National Natural Science Foundation of China (Grant No 60667001)
文摘We propose a scheme to implement the n-qubit Deutsch-Jozsa algorithm based on resonant interaction between the atoms and a single-mode cavity. In the scheme, the resonant transitions between two ground states and one excited state of an atom are changed alternately by adjusting the cavity frequency appropriately, and the operations required to complete the algorithm can be significantly simplified following the increment of the number of qubits. The implementation of the scheme in experiment would show the full power of quantum algorithm and would be significative and important for more complicated quantum algorithm in cavity quantum electrodynamics.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 11047182,11165008,and 11065007)the Natural Science Foundation of Jiangxi Province,China (Grant Nos. 20114BAB202001 and 2010GQW0011)the Science Foundation of East China Jiaotong University,China (Grant Nos. 10JC03 and 10JC06)
文摘In this paper we propose a scheme in which two-mode entanglement in a steady state is produced by using two lasers to resonantly drive a single four-level atom embedded inside a two-mode optical cavity. In this scheme, atomic coherence induced by a classical laser plays an important role in the process of preparing the entangled state. With the coupling of a strong control field, direct two-photon transition is generated and the relatively weak pump field induces the parametric interaction between two photons, which makes them entangle with each other. By numerical calculation, we find that the degree of entanglement depends strongly on the Rabi frequencies of the classical laser fields and the cavity losses.
基金Project supported by the National Natural Science Foundation of China (Grant No. 10674025)the Doctoral Foundation of the Ministry of Education of China (Grant No. 20070386002)
文摘This paper proposes a scheme for generating arbitrary superpositions of several coherent states along a straight line for a cavity mode. In the scheme, several atoms are sent through a cavity initially in a strong coherent state. The superposition of several coherent states with desired coefficients may be generated if each atom is detected in the excited state after it exits the cavity. The scheme is based on resonant atom-cavity interaction and no classical field is required during and after the atom cavity interaction. Thus, the scheme is very simple and the interaction time is very short, which is important in view of decoherence.
基金supported by the National Natural Science Foundation of China(Grant Nos.11347215,11464014,and 11104113)the Natural Science Foundation of Hunan Province,China(Grant Nos.13JJ6059 and 13JJB015)the Natural Science Foundation of Education Department of Hunan Province,China(Grant Nos.13C750 and 13B091)
文摘We use the photon Green-function method to study the quantum resonant dipole-dipole interaction(RDDI) induced by an Ag nanosphere(ANP).As the distance between the two dipoles increases,the RDDI becomes weaker,which is accompanied by the influence of the higher-order mode of the ANP on RDDI declining more quickly than that of the dipole mode.Across a broad frequency range(above 0.05 eV),the transfer rate of the RDDI is nearly constant since the two dipoles are fixed at the proper position.In addition,this phenomenon still exists for slightly different radius of the ANPs.We find that the frequency corresponding to the maximum transfer rate of RDDI exhibits a monotonic decrease by moving away one dipole as the other dipole and the ANP are kept fixed.In addition,the radius of ANP has little effect on this.When the two dipoles are far from the ANP,the maximum transfer rate of the RDDI takes place at the frequency of the dipole mode.In contrast,when the two dipoles are close to the ANP,the higher-order modes come into effect and they will play a leading role in the RDDI if they match the transition frequency of the dipole.Our results may be used in a biological detector and have a certain guiding significance for further application.
基金Supported by the National Natural Science Foundation of China under Grant No 60667001, and the Education Foundation of Yanbian University.
文摘A scheme for implementing a two-qubit phase gate with atoms sent through a high-Q optical cavity is proposed by choosing nonidentical coupling constants between the atoms and cavity. The atomic spontaneous emission can be suppressed due to the large atom-field detuning. Moreover, the scheme can be generalized to implement an N-qubit phase gate and the gating time does not change with an increase of the number of qubits.
文摘A scheme is proposed for generating entangled W states with four cavity modes. In this scheme, we send a V-type three-level atom through two identical two-mode cavities in succession. After the atom exits from the second cavity, the four cavity modes are prepared in the W state. On the other hand we can obtain three-atom W states by sending three V-type three-level atoms through a two-mode cavity in turn. The present scheme does not require conditional measurement, and it is easily generalized to preparing 2n-mode W states and n-atom W states.
文摘The existence of specific biorhythms and the role of geomagnetic and/or solar magnetic activities are well-established by appropriate correlations in chronobiology. From a physical viewpoint, there are two different accesses to biorhythms to set up connections to molecular processes: quantum mechanical perturbation theoretical methods and their resonance dominators to characterize specific interactions between constituents. These methods permit the treatment of molecular processes by circuits with characteristic resonances and “beat-frequencies”, which result from primarily fast physical processes. As examples, the tunneling processes between DNA base pairs (H bonds), the ATP decomposition and the irradiation of tumor cells are accounted for.
基金supported by National Natural Science Foundation of China (Grant No 10674025)the Development Funds of Fuzhou University of China (Grant No 2007-XY-15)
文摘This paper proposes an alternative scheme for generating four-photon W state via cavity QED. The scheme bases on the resonant interaction of a A-type three level atom with two bimodal cavities. The detection of atom collapses the cavity to the desired state. Comparing with previous schemes, the advantage of this scheme is that the interaction time can be greatly shortened since it uses the resonant interaction between atom and cavities. Moreover, the proposed scheme is more experimentally feasible than the previous ones.
基金Project supported by the National Natural Science Foundation of China(Grant Nos10574022 and 10575022)the Funds of the Natural Science of Fujian Province,China(Grant Nos Z0512006 and A0210014)
文摘This paper proposes a scheme for the implementation of 1→ 3 optimal phase-covariant quantum cloning with trapped ions. In the present protocol, the required time for the whole procedure is short due to the resonant interaction, which is important in view of decoherence. Furthermore, the scheme is feasible based on current technologies.
文摘Free surface waves in a cylinder of liquid under vertical excitation with slowly modulated amplitude are investigated in the current paper. It is shown by both theoretical analysis and numerical simulation that chaos may occur even for a single mode with modulation which can be used to explain Gollub and Meyer's experiment. The implied resonant mechanism accounting for this phenomenon is further elucidated.
基金Project supported by funds from the State Key Laboratory Breeding Base of Photocatalysis,Fuzhou University
文摘This paper proposes a decoherence-immune scheme for generating highly entangled states for two atoms trapped in a cavity. The scheme is based on two resonant atom-cavity interactions. Conditional upon the detection of no photon, the two atoms may exchange an excitation via the first resonant interaction, which leads to entanglement. Due to the loss of the excitation, the two atoms are in a mixed entangled state. With the help of an auxiliary ground state not coupled to the cavity mode, the state related to the excitation loss is eliminated by the detection of a photon resulting from the second resonant interaction. Thus, the fidelity of entanglement is almost not affected by the decoherence.
基金Supported by the Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou)(No.GML2019ZD0304)the National Natural Science Foundation of China(Nos.41630970,41876016,41676022,41521005)+2 种基金the Natural Science Foundation of Zhejiang(No.LR20D060001)the Instrument Developing Project of the CAS(No.YZ201432)the State Key Laboratory of Tropical Oceanography,South China Sea Institute of Oceanology,Chinese Academy of Sciences(No.LTO1915)。
文摘Near-diurnal vertically-standing waves with high vertical wavenumbers k z were observed in the velocity and shear fi elds from a set of 75-d long ADCP moored in the northeastern South China Sea(SCS)away from the“critical”latitude of 28.8°.These enhanced near-diurnal internal waves followed a fortnightly spring-neap cycle.However,they always happened during semidiurnal spring tides rather than diurnal springs although strong diurnal internal tides with the fortnightly spring-neap cycle were prevailing,suggesting that they were generated via subharmonic instability(PSI)of dominant semidiurnal M 2 internal tides.When two semidiurnal internal tidal waves with opposite vertical propagation direction intersected,both semidiurnal subharmonic and super harmonic waves were largely intensifi ed.The observed maximum diurnal velocity amplitudes were up to 0.25 m/s.The kinetic energy and shear spectra further suggested that frequencies of daughter waves were not always perfectly equal to M 2/2.The superposition of two daughter waves with nearly equal frequencies and nearly opposite k z in a PSI-triad leaded to the vertically-standing waves.
基金supported by the Natural Science Foundation of Fujian Province of China (Grant No T0650007)Funds from Education Department of Fujian Province of China (Grant No JB06041)
文摘This paper presents a method for generating entanglement molecules, which is introduced by Dur (2001 Phys. Rev. A). In this scheme, N ladder-type three-level atoms are sent through a resonant weak coherent cavity field, then the system states are measured. And the system field may collapse onto some possible types of entanglement molecules. Meanwhile it discusses about the interaction time from the experimental point of view, and compare the result with the previous scheme proposed by Huang (2004 J. Phys. B: At. Mol. Opt. Phys.).
基金Supported by the National Natural Science Foundation of China under Grant No 11105001the Anhui Provincial Natural Science Foundation under Grant Nos 1408085QA22 and 1608085MA09
文摘The single photon scattering properties in a pair of waveguides coupled by a whispering-gallery resonator in- teracting with a semiconductor quantum dot are investigated theoretically. The two waveguides support four possible ports for an incident single photon. The quantum dot is considered a V-type system. The incident direction-dependent single photon scattering properties are studied and equal-output probability from the four ports for a single photon incident is discussed. The influences of backscattering between the two modes of the whispering-gallery resonator for incident direction-dependent single photon scattering properties are also pre- sented.
基金supported by National Natural Science Foundation of China(Nos.11505040,11261140326,11405038 and 51577043)China Postdoctoral Science Foundation(Nos.2016M591518,2015M570283)HIT.NSRIF under Grant No.2017008
文摘Dipole Research EXperiment(DREX) is a new terrella device as part of the Space Plasma Environment Research Facility(SPERF) for laboratory studies of space physics relevant to the inner magnetospheric plasmas. Adequate plasma sources are very important for DREX to achieve its scientific goals. According to different research requirements, there are two density regimes for DREX. The low density regime will be achieved by an electron cyclotron resonance(ECR) system for the ‘whistler/chorus' wave investigation, while the high density regime will be achieved by biased cold cathode discharge for the desired ‘Alfvén' wave study. The parameters of ‘whistler/chorus' waves and ‘Alfvén' waves are determined by the scaling law between space and laboratory plasmas in the current device. In this paper, the initial design of these two plasma sources for DREX is described. Focus is placed on the chosen frequency and operation mode of the ECR system which will produce relatively low density ‘artificial radiation belt' plasmas and the seed electrons, followed by the design of biased cold cathode discharge to generate plasma with high density.