Gao, YB , Beijing Univ Technol, Coll Appl Sci, Beijing 100022, Peoples R China
部门归属:
Beijing Univ Technol, Coll Appl Sci, Beijing 100022, Peoples R China; Chinese Acad Sci, Inst Theoret Phys, Beijing 100080, Peoples R China
英文摘要:
The fluctuation-dissipation relation is well known for a quantum open system with energy dissipation. In this paper a similar underlying relation is found between the bath fluctuation and the dephasing of the quantum open system, for which energy is conserved, but the information is leaking into the bath. To obtain this relation we revisit the universal, but simple dephasing model with a quantum nondemolition interaction between the bath and the open system. Then we show that the decoherence factor describing the dephasing process is factorized into two parts, to indicate the two sources of dephasing, the vacuum quantum fluctuation, and the thermal excitations defined in the initial state of finite temperature.