Quantum entanglement plays a key role in both understanding the fundamental aspects of quantum physics and realizing various quantum devices for practical applications. Here we propose how to achieve a coherent switch...Quantum entanglement plays a key role in both understanding the fundamental aspects of quantum physics and realizing various quantum devices for practical applications. Here we propose how to achieve a coherent switch of optomechanical entanglement in an optical whispering-gallery-mode resonator, by tuning the phase difference of the driving lasers. We find that the optomechanical entanglement and the associated two-mode quantum squeezing can be well tuned in a highly asymmetric way,providing an efficient way to protect and enhance quantum entanglement against optical backscattering, in comparison with conventional symmetric devices. Our findings shed a new light on improving the performance of various quantum devices in the practical noisy environment, which is crucial in such a wide range of applications as noise-tolerant quantum processing and the backscattering-immune quantum metrology.展开更多
Schrödinger cat states,consisting of superpositions of macroscopically distinct states,provide key resources for a large number of emerging quantum technologies in quantum information processing.Here we propose h...Schrödinger cat states,consisting of superpositions of macroscopically distinct states,provide key resources for a large number of emerging quantum technologies in quantum information processing.Here we propose how to generate and manipulate mechanical and optical Schrödinger cat states with distinguishable superposition components by exploiting the unique properties of cavity optomechanical systems based on Bose-Einstein condensate.Specifically,we show that in comparison with its solid-state counterparts,almost a 3 order of magnitude enhancement in the size of the mechanical Schrödinger cat state could be achieved,characterizing a much smaller overlap between its two superposed coherent-state components.By exploiting this generated cat state,we further show how to engineer the quadrature squeezing of the mechanical mode.Besides,we also provide an efficient method to create multicomponent optical Schrödinger cat states in our proposed scheme.Our work opens up a new way to achieve nonclassical states of massive objects,facilitating the development of fault-tolerant quantum processors and sensors.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.11935006,11774086,12147156,12125402,1197502612064010)+3 种基金supported by the Science and Technology Innovation Program of Hunan Province(Grant No.2020RC4047)supported by the China Postdoctoral Science Foundation(Grant Nos.2021M701176,and 2022T150208)the Science and Technology Innovation Program of Hunan Province(Grant No.2021RC2078)supported by the Natural Science Foundation of Hunan Province(Grant No.2021JJ20036)。
文摘Quantum entanglement plays a key role in both understanding the fundamental aspects of quantum physics and realizing various quantum devices for practical applications. Here we propose how to achieve a coherent switch of optomechanical entanglement in an optical whispering-gallery-mode resonator, by tuning the phase difference of the driving lasers. We find that the optomechanical entanglement and the associated two-mode quantum squeezing can be well tuned in a highly asymmetric way,providing an efficient way to protect and enhance quantum entanglement against optical backscattering, in comparison with conventional symmetric devices. Our findings shed a new light on improving the performance of various quantum devices in the practical noisy environment, which is crucial in such a wide range of applications as noise-tolerant quantum processing and the backscattering-immune quantum metrology.
基金supported by the National Natural Science Foundation of China(NSFC)(11935006 and 11774086)the Science and Technology Innovation Program of Hunan Province(2020RC4047)+6 种基金L.-M.K.was supported by the NSFC(1217050862,11935006 and 11775075)X.-W.X.was supported by the NSFC(12064010)Natural Science Foundation of Hunan Province of China(2021JJ20036)Y.-F.J.was supported by the NSFC(12147156)the China Postdoctoral Science Foundation(2021M701176)the Science and Technology Innovation Program of Hunan Province(2021RC2078)B.J.L.was supported by Postgraduate Scientific Research Innovation Project of Hunan Province(CX20210471).
文摘Schrödinger cat states,consisting of superpositions of macroscopically distinct states,provide key resources for a large number of emerging quantum technologies in quantum information processing.Here we propose how to generate and manipulate mechanical and optical Schrödinger cat states with distinguishable superposition components by exploiting the unique properties of cavity optomechanical systems based on Bose-Einstein condensate.Specifically,we show that in comparison with its solid-state counterparts,almost a 3 order of magnitude enhancement in the size of the mechanical Schrödinger cat state could be achieved,characterizing a much smaller overlap between its two superposed coherent-state components.By exploiting this generated cat state,we further show how to engineer the quadrature squeezing of the mechanical mode.Besides,we also provide an efficient method to create multicomponent optical Schrödinger cat states in our proposed scheme.Our work opens up a new way to achieve nonclassical states of massive objects,facilitating the development of fault-tolerant quantum processors and sensors.