Master equation describing the diffusion process for a coherent state  

作　　者：刘堂昆 单传家 刘继兵 范洪义 

机构地区：[1]College of Physics and Electronic Science, Hubei Normal University [2]Department of Material Science and Engineering, University of Science and Technology of China

出　　处：《Chinese Physics B》2014年第3期112-114,共3页中国物理B（英文版）

基　　金：Project supported by the National Basic Research Program of China(Grant No.2012CB922103);the National Natural Science Foundation of China(GrantNos.11175113 and 11274104);the Natural Science Foundation of Hubei Province of China(Grant No.2011CDA021)

摘　　要：The evolution of a pure coherent state into a chaotic state is described very well by a master equation, as is validated via an examination of the coherent state＇s evolution during the diffusion process, fully utilizing the technique of integration within an ordered product （IWOP） of operators. The same equation also describes a limitation that maintains the coherence in a weak diffusion process, i.e., when the dissipation is very weak and the initial average photon number is large. This equation is dp/dt = -κ[a＋ap -a＋pa -apa＋ ＋ paa＋]. The physical difference between this diffusion equation and the better-known amplitude damping master equation is pointed out.The evolution of a pure coherent state into a chaotic state is described very well by a master equation, as is validated via an examination of the coherent state＇s evolution during the diffusion process, fully utilizing the technique of integration within an ordered product （IWOP） of operators. The same equation also describes a limitation that maintains the coherence in a weak diffusion process, i.e., when the dissipation is very weak and the initial average photon number is large. This equation is dp/dt = -κ[a＋ap -a＋pa -apa＋ ＋ paa＋]. The physical difference between this diffusion equation and the better-known amplitude damping master equation is pointed out.

关 键 词：master equation describing diffusion coherent state evolution chaotic state integration within anordered product （IWOP） of operators 

分 类 号：O552.2[理学—热学与物质分子运动论]