Title: Thermodynamic Roles of Quantum Environments: From Heat Baths to Work Reservoirs Show Chinese title

Title: 量子环境的热力学作用：从热浴到功库

Abstract: Environments in quantum thermodynamics usually take the role of heat baths. These baths are Markovian, weakly coupled to the system, and initialized in a thermal state. Whenever one of these properties is missing, standard quantum thermodynamics is no longer suitable to treat the thermodynamic properties of the system that result from the interaction with the environment. Using a recently proposed framework for open system quantum thermodynamics which is valid for arbitrary couplings and non-Markovian effects, we show that within the very same model, described by a Fano-Anderson Hamiltonian, the environment can take three different thermodynamic roles: a standard heat bath, exchanging only heat with the system, a work reservoir, exchanging only work, and a hybrid environment, providing both types of energy exchange. The exact role of the environment is determined by the strength and structure of the coupling, and by its initial state. The latter also dictates the long time behaviour of the open system, leading to thermal equilibrium for an initial thermal state and to a nonequilibrium steady state when there are displaced environmental modes. Show Chinese abstract

Abstract: 量子热力学中的环境通常扮演着热库的角色。这些热库是马尔可夫的、与系统弱耦合，并且初始处于热平衡态。只要上述任一特性缺失，标准量子热力学就不再适用于描述由系统与环境相互作用所导致的热力学性质。利用最近提出的适用于任意耦合和非马尔可夫效应的开放系统量子热力学框架，我们证明了在同一个由Fano-Anderson哈密顿量描述的模型中，环境可以扮演三种不同的热力学角色：一个标准热库，仅与系统交换热量；一个功库，仅与系统交换功；以及一个混合环境，同时提供两种能量交换。环境的具体角色由耦合的强度和结构以及其初始状态决定。后者还决定了开放系统的长期行为，当初始状态为热平衡态时会导致热平衡，而当存在位移的环境模式时则会导致非平衡稳态。