The dynamic control of single-photon scattering in a pair of one-dimensional waveguides mediated by a time-modulated atom-cavity system is investigated.Two cases,where the waveguides are coupled symmetrically or asymm...The dynamic control of single-photon scattering in a pair of one-dimensional waveguides mediated by a time-modulated atom-cavity system is investigated.Two cases,where the waveguides are coupled symmetrically or asymmetrically to the atom-cavity system,are discussed in detail.The results show that such time-modulated atom-cavity configuration can behave as a dynamical tunable directional single-photon router.The photons with different frequencies can dynamically be routed from the incident waveguide into any ports of the other with a 100%probability via adjusting the modulated amplitude or phases of the time-modulated atom-cavity coupling strengths,associate with the help of the asymmetrical waveguide-cavity couplings.Furthermore,the influence of dissipation on the routing capability is investigated.It is shown that the present single-photon router is robust against the dissipative process of the system,especially the atomic dissipation.These results are expected to be applicable in quantum information processing and design quantum devices with dynamical modulation.展开更多
It is well known that squeezed states can be produced by nonlinear optical processes,such as parametric amplification and four wave mixing,in which two photons are created or annihilated simultaneously.Since the Hamil...It is well known that squeezed states can be produced by nonlinear optical processes,such as parametric amplification and four wave mixing,in which two photons are created or annihilated simultaneously.Since the Hamiltonian of the dynamic Casimir effect contains a~2 and a~(+2),photons in such a process are also generated or annihilated in pairs.Here we propose to get squeezed light through the dynamic Casimir effect.Specifically,we demonstrate it from the full quantum perspective and the semiclassical perspective successively.Different from previous work,we focus on generating squeezed states with the lowest average photon number,because such squeezed states have better quantum properties.For the full quantum picture,that is,phonons also have quantum properties,when the system is initially in the excited state of phonons,squeezed light cannot be generated during the evolution,but the light field can collapse to the squeezed state by measuring the state of phonons.When the phonon is treated as a classical quantity,that is,the cavity wall is continuously driven,squeezed light with the minimum average photon number will be generated in the case of off-resonance.This will play a positive role in better regulating the photon state generated by the dynamic Casimir system in the future.展开更多
基金Project supported by China Postdoctoral Science Foundation (Grant No.2023M732028)the Fund from Zhejiang Province Key Laboratory of Quantum Technology and Device (Grant No.20230201)+3 种基金the Fundamental Research Funds for the Provincial Universities of Zhejiang Province,China (Grant No.GK199900299012-015)the Natural Science Foundation of Zhejiang Province,China (Grant No.LY21A040003)the National Natural Science Foundation of China (Grant Nos.12164022,12174288,and 12274326)the Natural Science Foundation of Jiangxi Province,China (Grant No.20232BAB201044)。
文摘The dynamic control of single-photon scattering in a pair of one-dimensional waveguides mediated by a time-modulated atom-cavity system is investigated.Two cases,where the waveguides are coupled symmetrically or asymmetrically to the atom-cavity system,are discussed in detail.The results show that such time-modulated atom-cavity configuration can behave as a dynamical tunable directional single-photon router.The photons with different frequencies can dynamically be routed from the incident waveguide into any ports of the other with a 100%probability via adjusting the modulated amplitude or phases of the time-modulated atom-cavity coupling strengths,associate with the help of the asymmetrical waveguide-cavity couplings.Furthermore,the influence of dissipation on the routing capability is investigated.It is shown that the present single-photon router is robust against the dissipative process of the system,especially the atomic dissipation.These results are expected to be applicable in quantum information processing and design quantum devices with dynamical modulation.
基金supported by the National Natural Science Foundation of China (Grant Nos.12174288,12274326,and 12204352)the National Key R&D Program of China (Grant No.2021YFA1400602)。
文摘It is well known that squeezed states can be produced by nonlinear optical processes,such as parametric amplification and four wave mixing,in which two photons are created or annihilated simultaneously.Since the Hamiltonian of the dynamic Casimir effect contains a~2 and a~(+2),photons in such a process are also generated or annihilated in pairs.Here we propose to get squeezed light through the dynamic Casimir effect.Specifically,we demonstrate it from the full quantum perspective and the semiclassical perspective successively.Different from previous work,we focus on generating squeezed states with the lowest average photon number,because such squeezed states have better quantum properties.For the full quantum picture,that is,phonons also have quantum properties,when the system is initially in the excited state of phonons,squeezed light cannot be generated during the evolution,but the light field can collapse to the squeezed state by measuring the state of phonons.When the phonon is treated as a classical quantity,that is,the cavity wall is continuously driven,squeezed light with the minimum average photon number will be generated in the case of off-resonance.This will play a positive role in better regulating the photon state generated by the dynamic Casimir system in the future.
