We propose a scheme to generate a three-qubit three-IeveI singlet state in cavity QED, by placing three A-type SQUIDs in a single mode cavity. In this scheme, we make use of the interaction between the SQUIDs and cavi...We propose a scheme to generate a three-qubit three-IeveI singlet state in cavity QED, by placing three A-type SQUIDs in a single mode cavity. In this scheme, we make use of the interaction between the SQUIDs and cavity filed, and the classical pulses. The cavity fields are in vacuum state during the whole operation processes of creating the entanglement, and there is no quantum information transformation between the SQUIDs and cavity fields. Because of the advantage of the SQUID-cavity system, the quality factor of the cavity is greatly relaxed.展开更多
We consider the energy operator of six-electron systems in the Hubbard model and investigate the structure of essential spectra and discrete spectrum of the system in the first quintet and first singlet states in the ...We consider the energy operator of six-electron systems in the Hubbard model and investigate the structure of essential spectra and discrete spectrum of the system in the first quintet and first singlet states in the v-dimensional lattice.展开更多
We propose an adiabatic-passage scheme for the generation of three-qutrit singlet states with two-level trapped ions. Distinctly different from previous proposals, we encode qutrits in Dicke states with two-level ions...We propose an adiabatic-passage scheme for the generation of three-qutrit singlet states with two-level trapped ions. Distinctly different from previous proposals, we encode qutrits in Dicke states with two-level ions and use the adiabatic-evolution techniques in order not to exactly control the laser pulses, making the realization of the scheme much easier. Furthermore, the phonon is only virtually excited in the procedure, so the effect of the phonon losses can be reduced.展开更多
A proposal for the generation of singlet states of three A-type Rydberg atoms is presented via the interaction between a separate Rydberg state and an EPR pair. Different from previous schemes, we do not need to coupl...A proposal for the generation of singlet states of three A-type Rydberg atoms is presented via the interaction between a separate Rydberg state and an EPR pair. Different from previous schemes, we do not need to couple ground states by using microwave lights but to set appropriate frequency detuning between lasers and two atomic transitions between ground states and Rydberg levels to eliminate the degenerate of the two ground states, making the present protocol more easily in experiment. Moreover, a series of numerical simulations are made to show the feasibility.展开更多
We analyze the spin coincidence experiment considered by Bell in the derivation of Bells theorem. We solve the equation of motion for the spin system with a spin Hamiltonian, Hz, where the magnetic field is only in th...We analyze the spin coincidence experiment considered by Bell in the derivation of Bells theorem. We solve the equation of motion for the spin system with a spin Hamiltonian, Hz, where the magnetic field is only in the z-direction. For the specific case of the coincidence experiment where the two magnets have the same orientation the Hamiltonian Hz commutes with the total spin Iz, which thus emerges as a constant of the motion. Bells argument is then that an observation of spin up at one magnet A necessarily implies spin down at the other B. For an isolated spin system A-B with classical translational degrees of freedom and an initial spin singlet state there is no force on the spin particles A and B. The spins are fully entangled but none of the spin particles A or B are deflected by the Stern-Gerlach magnets. This result is not compatible with Bells assumption that spin 1/2 particles are deected in a Stern-Gerlach device. Assuming a more realistic Hamiltonian Hz + Hx including a gradient in x direction the total Iz is not conserved and fully entanglement is not expected in this case. The conclusion is that Bells theorem is not applicable to spin coincidence measurement originally discussed by Bell.展开更多
We have presented the synthesis and characterization of three new bromo substituted stilbene derivatives, p-3,4,5-trimethoxy-p′- 2,3,4,5,6-pentabromostilbene （C1）, p-N,N-dimethylamino-p′-2,3,4,5,6-pentabromostilbe...We have presented the synthesis and characterization of three new bromo substituted stilbene derivatives, p-3,4,5-trimethoxy-p′- 2,3,4,5,6-pentabromostilbene （C1）, p-N,N-dimethylamino-p′-2,3,4,5,6-pentabromostilbene （C2） and p-N,N-diphenylamino-p′- 2,3,4,5,6-pentabromostilbene （C3） in this letter. The UV/vis absorption and photoluminescence were investigated in various solvents. The maximal absorption wavelength of C1 exhibited blue-shift to those of C2 and C3 in different solvents. No florescence emission could be detected for these compounds at room temperature. Singlet oxygen could be efficiently produced with these sensitizers under near-ultraviolet and visible light irradiation.展开更多
We consider the energy operator of four-electron systems in an impurity Hubbard model and investigated the structure of essential spectra and discrete spectrum of the system in the first triplet state in a one-dimensi...We consider the energy operator of four-electron systems in an impurity Hubbard model and investigated the structure of essential spectra and discrete spectrum of the system in the first triplet state in a one-dimensional lattice. For investigation the structure of essential spectra and discrete spectrum of the energy operator of four-electron systems in an impurity Hubbard model, for which the momentum representation is convenient. In addition, we used the tensor products of Hilbert spaces and tensor products of operators in Hilbert spaces and described the structure of essential spectrum and discrete spectrum of the energy operator of four-electron systems in an impurity Hubbard model. The investigations show that there are such cases: 1) the essential spectrum of the system consists of the union of no more than eight segments, and the discrete spectrum of the system consists of no more than three eigenvalues;2) the essential spectrum of the system consists of the union of no more than sixteen segments, and the discrete spectrum of the system consists of no more than eleven eigenvalues;3) the essential spectrum of the system consists of the union of no more than three segments, and the discrete spectrum of the system is the empty set. Consequently, the essential spectrum of the system consists of the union of no more than sixteen segments, and the discrete spectrum of the system consists of no more than eleven eigenvalues.展开更多
We consider an energy operator of four-electron system in the Impurity Hubbard model with a coupling between nearest-neighbors. The spectrum of the systems in the second triplet state in a ν-dimensional lattice is in...We consider an energy operator of four-electron system in the Impurity Hubbard model with a coupling between nearest-neighbors. The spectrum of the systems in the second triplet state in a ν-dimensional lattice is investigated. For investigation the structure of essential spectra and discrete spectrum of the energy operator of four-electron systems in an impurity Hubbard model, for which the momentum representation is convenient. In addition, we used the tensor products of Hilbert spaces and tensor products of operators in Hilbert spaces and described the structure of essential spectrum and discrete spectrum of the energy operator of four-electron systems in an impurity Hubbard model for the second triplet state of the system. The investigations show that the essential spectrum of the system consists of the union of no more than sixteen segments, and the discrete spectrum of the system consists of no more than eleven eigenvalues.展开更多
This work presents results of the different parameters which characterize the nonrelativistic Hamilton operator for the helium atoms allowing us to solve the Schrödinger equation. The total energy is decomposed i...This work presents results of the different parameters which characterize the nonrelativistic Hamilton operator for the helium atoms allowing us to solve the Schrödinger equation. The total energy is decomposed into three terms allowing to separate the kinetic energy, the electrons-nucleus interaction energy and the electron-electron interaction energy of the (2s<sup>2</sup>, 3s<sup>2</sup> and 4s<sup>2</sup>) <sup>1</sup>S<sup>e</sup>, (2p<sup>2</sup>, 3p<sup>2</sup> and 4p<sup>2</sup>) <sup>1</sup>D<sup>e</sup> and (3d<sup>2</sup> and 4d<sup>2</sup>) <sup>1</sup>G<sup>e</sup> resonance singlet states of the helium isoelectronic sequences. The states have been defined by using special forms of the Hylleraas type wave functions. The calculations have been carried out in the framework of the variational method using configuration interaction basis states with a real Hamiltonian. The agreement of the energy value of other states between the present theoretical values available in the literature is excellent. But as for the comparison of the kinetic energies, the electrons-nucleus energies interaction and the electron-electron interaction energies, we note a slight difference with the theoretical values common in literature.展开更多
The structure and mechanism of isomerization of CH3SB have been studied by using DFT method at the B3LYP/6-311G** level. The computational results reveal that the energy of singlet state of CH3SB is lower than that ...The structure and mechanism of isomerization of CH3SB have been studied by using DFT method at the B3LYP/6-311G** level. The computational results reveal that the energy of singlet state of CH3SB is lower than that of triplet state, so the former should be the ground state. Two transition states of isomerization of singlet state of CH3SB have been determined at the B3L-YP/6- 311G** level, too. The methyl linked to sulfur atom is first transferring to the boron atom, to which the hydrogen atom of methyl is then transferring. According to the results of this paper, reaction paths of isomerizations of CH3SB are studied thoroughly with IRC method.展开更多
We consider two-electron systems for the impurity Hubbard Model and investigate the spectrum of the system in a singlet state for the v-dimensional integer valued lattice Z<sup>v</sup>. We proved the essen...We consider two-electron systems for the impurity Hubbard Model and investigate the spectrum of the system in a singlet state for the v-dimensional integer valued lattice Z<sup>v</sup>. We proved the essential spectrum of the system in the singlet state is consists of union of no more then three intervals, and the discrete spectrum of the system in the singlet state is consists of no more then five eigenvalues. We show that the discrete spectrum of the system in the triplet and singlet states differ from each other. In the singlet state the appear additional two eigenvalues. In the triplet state the discrete spectrum of the system can be empty set, or is consists of one-eigenvalue, or is consists of two eigenvalues, or is consists of three eigenvalues. For investigation the structure of essential spectra and discrete spectrum of the energy operator of two-electron systems in an impurity Hubbard model, for which the momentum representation is convenient. In addition, we used the tensor products of Hilbert spaces and tensor products of operators in Hilbert spaces and described the structure of essential spectrum and discrete spectrum of the energy operator of two-electron systems in an impurity Hubbard model.展开更多
基金Supported by the Natural Science Foundation of China under Grant No.60677044
文摘We propose a scheme to generate a three-qubit three-IeveI singlet state in cavity QED, by placing three A-type SQUIDs in a single mode cavity. In this scheme, we make use of the interaction between the SQUIDs and cavity filed, and the classical pulses. The cavity fields are in vacuum state during the whole operation processes of creating the entanglement, and there is no quantum information transformation between the SQUIDs and cavity fields. Because of the advantage of the SQUID-cavity system, the quality factor of the cavity is greatly relaxed.
文摘We consider the energy operator of six-electron systems in the Hubbard model and investigate the structure of essential spectra and discrete spectrum of the system in the first quintet and first singlet states in the v-dimensional lattice.
基金Supported by National Natural Science Foundation of China under Grant Nos.61308012 and 61275215the Fujian Natural Science Foundation under Grant Nos.2013J01008 and 2012J01004the Fund from Fujian Educational Department under Grant Nos.JA14075,JB13021,and JB12014
文摘We propose an adiabatic-passage scheme for the generation of three-qutrit singlet states with two-level trapped ions. Distinctly different from previous proposals, we encode qutrits in Dicke states with two-level ions and use the adiabatic-evolution techniques in order not to exactly control the laser pulses, making the realization of the scheme much easier. Furthermore, the phonon is only virtually excited in the procedure, so the effect of the phonon losses can be reduced.
基金Supported by the National Natural Science Foundation of China under Grant Nos.11647069,61308012,and 61275215
文摘A proposal for the generation of singlet states of three A-type Rydberg atoms is presented via the interaction between a separate Rydberg state and an EPR pair. Different from previous schemes, we do not need to couple ground states by using microwave lights but to set appropriate frequency detuning between lasers and two atomic transitions between ground states and Rydberg levels to eliminate the degenerate of the two ground states, making the present protocol more easily in experiment. Moreover, a series of numerical simulations are made to show the feasibility.
文摘We analyze the spin coincidence experiment considered by Bell in the derivation of Bells theorem. We solve the equation of motion for the spin system with a spin Hamiltonian, Hz, where the magnetic field is only in the z-direction. For the specific case of the coincidence experiment where the two magnets have the same orientation the Hamiltonian Hz commutes with the total spin Iz, which thus emerges as a constant of the motion. Bells argument is then that an observation of spin up at one magnet A necessarily implies spin down at the other B. For an isolated spin system A-B with classical translational degrees of freedom and an initial spin singlet state there is no force on the spin particles A and B. The spins are fully entangled but none of the spin particles A or B are deflected by the Stern-Gerlach magnets. This result is not compatible with Bells assumption that spin 1/2 particles are deected in a Stern-Gerlach device. Assuming a more realistic Hamiltonian Hz + Hx including a gradient in x direction the total Iz is not conserved and fully entanglement is not expected in this case. The conclusion is that Bells theorem is not applicable to spin coincidence measurement originally discussed by Bell.
基金support from National Natural Science Foundation of China(Nos. 20776165,20702065,20872184)Key Foundation of Chongqing Science and Technology Commission"(No.CSTC 2008BA4020)+1 种基金"A Foundation for the Author of National Excellent Doctoral Dissertation of PR China(200735)"for financial supportsponsored by the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry as well(Nos.20071108-1, 20071108-5).
文摘We have presented the synthesis and characterization of three new bromo substituted stilbene derivatives, p-3,4,5-trimethoxy-p′- 2,3,4,5,6-pentabromostilbene （C1）, p-N,N-dimethylamino-p′-2,3,4,5,6-pentabromostilbene （C2） and p-N,N-diphenylamino-p′- 2,3,4,5,6-pentabromostilbene （C3） in this letter. The UV/vis absorption and photoluminescence were investigated in various solvents. The maximal absorption wavelength of C1 exhibited blue-shift to those of C2 and C3 in different solvents. No florescence emission could be detected for these compounds at room temperature. Singlet oxygen could be efficiently produced with these sensitizers under near-ultraviolet and visible light irradiation.
文摘We consider the energy operator of four-electron systems in an impurity Hubbard model and investigated the structure of essential spectra and discrete spectrum of the system in the first triplet state in a one-dimensional lattice. For investigation the structure of essential spectra and discrete spectrum of the energy operator of four-electron systems in an impurity Hubbard model, for which the momentum representation is convenient. In addition, we used the tensor products of Hilbert spaces and tensor products of operators in Hilbert spaces and described the structure of essential spectrum and discrete spectrum of the energy operator of four-electron systems in an impurity Hubbard model. The investigations show that there are such cases: 1) the essential spectrum of the system consists of the union of no more than eight segments, and the discrete spectrum of the system consists of no more than three eigenvalues;2) the essential spectrum of the system consists of the union of no more than sixteen segments, and the discrete spectrum of the system consists of no more than eleven eigenvalues;3) the essential spectrum of the system consists of the union of no more than three segments, and the discrete spectrum of the system is the empty set. Consequently, the essential spectrum of the system consists of the union of no more than sixteen segments, and the discrete spectrum of the system consists of no more than eleven eigenvalues.
文摘We consider an energy operator of four-electron system in the Impurity Hubbard model with a coupling between nearest-neighbors. The spectrum of the systems in the second triplet state in a ν-dimensional lattice is investigated. For investigation the structure of essential spectra and discrete spectrum of the energy operator of four-electron systems in an impurity Hubbard model, for which the momentum representation is convenient. In addition, we used the tensor products of Hilbert spaces and tensor products of operators in Hilbert spaces and described the structure of essential spectrum and discrete spectrum of the energy operator of four-electron systems in an impurity Hubbard model for the second triplet state of the system. The investigations show that the essential spectrum of the system consists of the union of no more than sixteen segments, and the discrete spectrum of the system consists of no more than eleven eigenvalues.
文摘This work presents results of the different parameters which characterize the nonrelativistic Hamilton operator for the helium atoms allowing us to solve the Schrödinger equation. The total energy is decomposed into three terms allowing to separate the kinetic energy, the electrons-nucleus interaction energy and the electron-electron interaction energy of the (2s<sup>2</sup>, 3s<sup>2</sup> and 4s<sup>2</sup>) <sup>1</sup>S<sup>e</sup>, (2p<sup>2</sup>, 3p<sup>2</sup> and 4p<sup>2</sup>) <sup>1</sup>D<sup>e</sup> and (3d<sup>2</sup> and 4d<sup>2</sup>) <sup>1</sup>G<sup>e</sup> resonance singlet states of the helium isoelectronic sequences. The states have been defined by using special forms of the Hylleraas type wave functions. The calculations have been carried out in the framework of the variational method using configuration interaction basis states with a real Hamiltonian. The agreement of the energy value of other states between the present theoretical values available in the literature is excellent. But as for the comparison of the kinetic energies, the electrons-nucleus energies interaction and the electron-electron interaction energies, we note a slight difference with the theoretical values common in literature.
文摘The structure and mechanism of isomerization of CH3SB have been studied by using DFT method at the B3LYP/6-311G** level. The computational results reveal that the energy of singlet state of CH3SB is lower than that of triplet state, so the former should be the ground state. Two transition states of isomerization of singlet state of CH3SB have been determined at the B3L-YP/6- 311G** level, too. The methyl linked to sulfur atom is first transferring to the boron atom, to which the hydrogen atom of methyl is then transferring. According to the results of this paper, reaction paths of isomerizations of CH3SB are studied thoroughly with IRC method.
文摘We consider two-electron systems for the impurity Hubbard Model and investigate the spectrum of the system in a singlet state for the v-dimensional integer valued lattice Z<sup>v</sup>. We proved the essential spectrum of the system in the singlet state is consists of union of no more then three intervals, and the discrete spectrum of the system in the singlet state is consists of no more then five eigenvalues. We show that the discrete spectrum of the system in the triplet and singlet states differ from each other. In the singlet state the appear additional two eigenvalues. In the triplet state the discrete spectrum of the system can be empty set, or is consists of one-eigenvalue, or is consists of two eigenvalues, or is consists of three eigenvalues. For investigation the structure of essential spectra and discrete spectrum of the energy operator of two-electron systems in an impurity Hubbard model, for which the momentum representation is convenient. In addition, we used the tensor products of Hilbert spaces and tensor products of operators in Hilbert spaces and described the structure of essential spectrum and discrete spectrum of the energy operator of two-electron systems in an impurity Hubbard model.
