We propose a scheme to implement ancilla-free 1 to 2 optimal phase covariant quantum cloning with atoms trapped in cavities.In the scheme the W-class state of three atoms,which are individually trapped in three spatia...We propose a scheme to implement ancilla-free 1 to 2 optimal phase covariant quantum cloning with atoms trapped in cavities.In the scheme the W-class state of three atoms,which are individually trapped in three spatially separated cavities,is deterministically generated.Then by the use of this W-class state and detection of the atomic state,an optimal ancilla-free 1 to 2 phase-covariant quantum cloning between two spatially separated trapped atoms can be realized.The scheme is robust for atomic spontaneous decay,cavity decay and photon leakage out of the fiber.In principle,an M+1-atom W-class state can be generated by using such an approach.Thus this scheme also can be generalized to implement 1 to M ancilla-free phase-covariant quantum cloning.展开更多
基金supported by the National Natural Science Foundation of China (Grant No.11074002)the Personal Development Foundation of Anhui Province (Grant No.2008Z018)
文摘We propose a scheme to implement ancilla-free 1 to 2 optimal phase covariant quantum cloning with atoms trapped in cavities.In the scheme the W-class state of three atoms,which are individually trapped in three spatially separated cavities,is deterministically generated.Then by the use of this W-class state and detection of the atomic state,an optimal ancilla-free 1 to 2 phase-covariant quantum cloning between two spatially separated trapped atoms can be realized.The scheme is robust for atomic spontaneous decay,cavity decay and photon leakage out of the fiber.In principle,an M+1-atom W-class state can be generated by using such an approach.Thus this scheme also can be generalized to implement 1 to M ancilla-free phase-covariant quantum cloning.
