Man Zhong-Xiao, Xia Yun-Jie
Shandong Provincial Key Laboratory of Laser Polarization and Information Technology, Department of Physics, Qufu Normal University, Qufu 273165, China.
Phys Rev E. 2017 Jul;96(1-1):012122. doi: 10.1103/PhysRevE.96.012122. Epub 2017 Jul 12.
The functions of the smallest self-contained thermal machine consisting of a single qutrit are studied when the weak internal coupling assumption is relaxed. It is shown that in the presence of one target to be cooled the strong coupling is not beneficial to the refrigeration. The reason is explained by examining the effect of the strong coupling on the contributions of all eigenstates transitions to the heat current of the related thermal reservoir. When acting simultaneously on two targets, the machine can be manipulated to implement distributed tasks on them, such as cooling one target and meanwhile heating another one, by adjusting the coupling strengths between the machine with the two targets. In particular, we show that the machine can realize temperature reversal for the two qubits, namely, the qubit that is coupled to the high temperature reservoir is refrigerated to a temperature below that of the qubit contacting with the low temperature reservoir.
当放宽弱内部耦合假设时，研究了由单个三量子比特组成的最小自包含热机的功能。结果表明，在存在一个待冷却目标的情况下，强耦合对制冷并无益处。通过研究强耦合对所有本征态跃迁对相关热库热流贡献的影响来解释其原因。当同时作用于两个目标时，通过调节热机与两个目标之间的耦合强度，可以操纵热机在它们上执行分布式任务，例如冷却一个目标同时加热另一个目标。特别地，我们表明该热机可以实现两个量子比特的温度反转，即与高温库耦合的量子比特被冷却到低于与低温库接触的量子比特的温度。
