By virtue of the density operator＇s P-representation in the coherent state representation, we derive a new quantum mechanical photon counting distribution formula. As its application, we calculate photon counting dis...By virtue of the density operator＇s P-representation in the coherent state representation, we derive a new quantum mechanical photon counting distribution formula. As its application, we calculate photon counting distributions for some given light fields. It is found that the pure squeezed state＇s photon counting distribution is related to the Legendre function, which is a new result.展开更多
The photon-added spin coherent state as a new kind of coherent state has been defined by iterated actions of the proper raising operator on the ordinary spin coherent state. In this paper, the quantum statistical prop...The photon-added spin coherent state as a new kind of coherent state has been defined by iterated actions of the proper raising operator on the ordinary spin coherent state. In this paper, the quantum statistical properties of photon-added spin coherent states such as photon number distribution, second-order correlation function and Wigner function are studied. It is found that the Wigner function shows the negativity in some regions and the second-order correlation function is less than unity. Therefore, the photon-added spin coherent state is a nonclassical state.展开更多
Based on step-by-step microscopic calculation, the regular pumping one-atom micromaser is studied when the cavity decay in interaction time is considered. By numerical simulation, the steady-state photon distribution ...Based on step-by-step microscopic calculation, the regular pumping one-atom micromaser is studied when the cavity decay in interaction time is considered. By numerical simulation, the steady-state photon distribution and mean photon number are presented, and influence of cavity loss in the interaction time on the micromaser discussed. It has been found that, for different loss in the interaction time, the discrepancy is large.展开更多
AD = 1 position-dependent mass approach to constructing nonlinear quantum states for a modified Coulomb potential is used to generate Gazeau–Klauder coherent states. It appears that their energy eigenvalues are scale...AD = 1 position-dependent mass approach to constructing nonlinear quantum states for a modified Coulomb potential is used to generate Gazeau–Klauder coherent states. It appears that their energy eigenvalues are scaled down by the quantum number and the nonlinearity coefficient. We study the basic properties of these states, which are found to be undefined on the whole complex plane, and some details of their revival structure are discussed.展开更多
In this paper, the two-mode excited squeezed vacuum state （TESVS） is studied by using the statistical method. By calculating the normalization of the TESVS, a new form of Jacobi polynomials and some new identities a...In this paper, the two-mode excited squeezed vacuum state （TESVS） is studied by using the statistical method. By calculating the normalization of the TESVS, a new form of Jacobi polynomials and some new identities are obtained. The photon number distribution of the TESVS is given and it is a simple form of Jacobi polynomials. Using the entangled state representation of Wigner operator, the Wigner function of the TESVS is obtainded and the variations of the Wigner function with the parameters m, n, and r are discussed. Here from the phase space point of view the TESVS can be well interpreted and described.展开更多
Extending the recent work completed by Fan et al. [Front. Phys. 9（1）, 74 （2014）] to a two-mode case, we investigate how a two-mode squeezed vacuum evolves when it undergoes a two-mode amplitude dissipative channel...Extending the recent work completed by Fan et al. [Front. Phys. 9（1）, 74 （2014）] to a two-mode case, we investigate how a two-mode squeezed vacuum evolves when it undergoes a two-mode amplitude dissipative channel, with the same decay rate ~, using the continuous-variable entangled state approach. Our analytical results show that the initial pure-squeezed vacuum state evolves into a definite mixed state with entanglement and squeezing, decaying over time as a result of amplitude decay. We also investigate the time evolutions of the photon number distribution, the Wigner function, and the optical tomogram in this channel. Our results indicate that the evolved photon number distribution is related to Jacobi polynomials, the Wigner function has a standard Gaussian distribution （corresponding to the vacuum） at long periods, losing its nonclassicality due to amplitude decay, and a larger squeezing leads to a longer decay time.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.11174114 and 11175113)the Research Foundation of Changzhou Institute of Technology,China(Grant No.YN1007)the Research Foundation of Education Department of Jiangxi Province,China(Grant No.GJJ10097)
文摘By virtue of the density operator＇s P-representation in the coherent state representation, we derive a new quantum mechanical photon counting distribution formula. As its application, we calculate photon counting distributions for some given light fields. It is found that the pure squeezed state＇s photon counting distribution is related to the Legendre function, which is a new result.
文摘The photon-added spin coherent state as a new kind of coherent state has been defined by iterated actions of the proper raising operator on the ordinary spin coherent state. In this paper, the quantum statistical properties of photon-added spin coherent states such as photon number distribution, second-order correlation function and Wigner function are studied. It is found that the Wigner function shows the negativity in some regions and the second-order correlation function is less than unity. Therefore, the photon-added spin coherent state is a nonclassical state.
文摘Based on step-by-step microscopic calculation, the regular pumping one-atom micromaser is studied when the cavity decay in interaction time is considered. By numerical simulation, the steady-state photon distribution and mean photon number are presented, and influence of cavity loss in the interaction time on the micromaser discussed. It has been found that, for different loss in the interaction time, the discrepancy is large.
文摘AD = 1 position-dependent mass approach to constructing nonlinear quantum states for a modified Coulomb potential is used to generate Gazeau–Klauder coherent states. It appears that their energy eigenvalues are scaled down by the quantum number and the nonlinearity coefficient. We study the basic properties of these states, which are found to be undefined on the whole complex plane, and some details of their revival structure are discussed.
基金The project supported by National Natural Science Foundation of China under Grant No.10574060the Natural Science Foundation of Shandong Province of China under Grant No.Y2004A09
文摘In this paper, the two-mode excited squeezed vacuum state （TESVS） is studied by using the statistical method. By calculating the normalization of the TESVS, a new form of Jacobi polynomials and some new identities are obtained. The photon number distribution of the TESVS is given and it is a simple form of Jacobi polynomials. Using the entangled state representation of Wigner operator, the Wigner function of the TESVS is obtainded and the variations of the Wigner function with the parameters m, n, and r are discussed. Here from the phase space point of view the TESVS can be well interpreted and described.
基金We are grateful to Prof. Hsi-Sheng Goan for valuable support during writing the paper. The project was supported by the National Natural Science Foundation of China （Grant No. 11347026） and the Natural Science Foundation of Shan- dong Province （Grant Nos. ZR2016AM03 and ZR2017MA011）.
文摘Extending the recent work completed by Fan et al. [Front. Phys. 9（1）, 74 （2014）] to a two-mode case, we investigate how a two-mode squeezed vacuum evolves when it undergoes a two-mode amplitude dissipative channel, with the same decay rate ~, using the continuous-variable entangled state approach. Our analytical results show that the initial pure-squeezed vacuum state evolves into a definite mixed state with entanglement and squeezing, decaying over time as a result of amplitude decay. We also investigate the time evolutions of the photon number distribution, the Wigner function, and the optical tomogram in this channel. Our results indicate that the evolved photon number distribution is related to Jacobi polynomials, the Wigner function has a standard Gaussian distribution （corresponding to the vacuum） at long periods, losing its nonclassicality due to amplitude decay, and a larger squeezing leads to a longer decay time.
