The heat and work of quantum thermodynamic processes with quantum coherence  

作　　者：Shanhe Su Jinfu Chen Yuhan Ma Jincan Chen Changpu Sun 苏山河;陈劲夫;马宇翰;陈金灿;孙昌璞(Beijing Computational Science Research Center,Beijing 100193,China;Department of Physics,Xiamen University,Xiamen 361005,China;Graduate School of the Chinese Academy of Engineering Physics,Beijing 100193,China)

机构地区：[1]Beijing Computational Science Research Center, Beijing 100193, China [2]Department of Physics, Xiamen University, Xiamen 361005, China [3]Graduate School of the Chinese Academy of Engineenng Physics, Beijing 100193, China

出　　处：《Chinese Physics B》2018年第6期195-202,共8页中国物理B（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.11421063,11534002,and 51776178);the National Key Basic Research Program of China(Grant Nos.2012CB922104 and 2014CB921403)

摘　　要：Energy is often partitioned into heat and work by two independent paths corresponding to the change in the eigenenergies or the probability distributions of a quantum system. The discrepancies of the heat and work for various quantum thermodynamic processes have not been well characterized in literature. Here we show how the work in quantum machines is differentially related to the isochoric, isothermal, and adiabatic processes. We prove that the energy exchanges during the quantum isochoric and isothermal processes are simply depending on the change in the eigenenergies or the probability distributions. However, for a time-dependent system in a non-adiabatic quantum evolution, the transitions between the different quantum states representing the quantum coherence can affect the essential thermodynamic properties, and thus the general definitions of the heat and work should be clarified with respect to the microscopic generic time-dependent system. By integrating the coherence effects in the exactly-solvable dynamics of quantum-spin precession, the internal energy is rigorously transferred as the work in the thermodynamic adiabatic process. The present study demonstrates that the quantum adiabatic process is sufficient but not necessary for the thermodynamic adiabatic process.Energy is often partitioned into heat and work by two independent paths corresponding to the change in the eigenenergies or the probability distributions of a quantum system. The discrepancies of the heat and work for various quantum thermodynamic processes have not been well characterized in literature. Here we show how the work in quantum machines is differentially related to the isochoric, isothermal, and adiabatic processes. We prove that the energy exchanges during the quantum isochoric and isothermal processes are simply depending on the change in the eigenenergies or the probability distributions. However, for a time-dependent system in a non-adiabatic quantum evolution, the transitions between the different quantum states representing the quantum coherence can affect the essential thermodynamic properties, and thus the general definitions of the heat and work should be clarified with respect to the microscopic generic time-dependent system. By integrating the coherence effects in the exactly-solvable dynamics of quantum-spin precession, the internal energy is rigorously transferred as the work in the thermodynamic adiabatic process. The present study demonstrates that the quantum adiabatic process is sufficient but not necessary for the thermodynamic adiabatic process.

关 键 词：heat and work thermodynamic adiabatic process quantum coherence 

分 类 号：O4[理学—物理]