Open AccessDecoherence of a photon-subtraction-addition coherent state in a thermal environment
Author(s) -
Haoliang Zhang,
Fang Jia,
Xue-Xiang Xu,
Qin Guo,
Tao Xiang-yang,
Li-Yun Hu
Publication year - 2013
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.62.014208
Subject(s) - wigner distribution function , quantum decoherence , physics , photon , coherent states , subtraction , quantum mechanics , function (biology) , time evolution , negativity effect , thermal , state (computer science) , statistical physics , quantum , mathematics , arithmetic , thermodynamics , evolutionary biology , biology , psychology , social psychology , algorithm
We investigate the nonclassicality and decoherence of a photon-subtraction-addition coherent state (a++a)m|a in a thermal environment. Its nonclassicality is discussed by deriving analytically Mandel's Q parameter, photon number distribution, and Wigner function. It is shown that if the condition |2z*+ -*|2 1 is satisfied, the Wigner function always presents the negativity for the one-order photon-subtraction-addition coherent state (m=1). Based on the evolution formula of Wigner function, we derive a compact expression for Wigner function in the thermal environment. It is found that when t(1/2)ln[(2N+2)/(2N+1)] there is no negativity for the case of m=1. In addition, the evolution of nonclassicality is discussed in terms of the negative volume of Wigner function.