Geometric properties of adiabatic quantum thermal machines
Geometric properties of adiabatic quantum thermal machines
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DOI：
10.1103/physrevb.102.155407
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发表时间：
2020-10-08
影响因子：
3.7
通讯作者：
Arrachea, Liliana
中科院分区：
文献类型：
--
作者：
Bhandari, Bibek;Terren Alonso, Pablo;Arrachea, Liliana
我们提出了一个通用的统一的方法来研究量子热机，包括热机和制冷机，在周期性绝热驱动下运行，并与保持在不同温度下的热库接触。我们表明，许多可观的特征，这种操作模式和机器的性能是几何性质的。热功转换机制和能量耗散可以分别由定义在时间相关参数空间中的热几何张量的反对称和对称分量来描述，所述时间相关参数空间被推广为包括温度偏差。反对称分量可以被识别为Berry曲率，而对称分量定义了流形的度量。我们表明，绝热热机器的操作，因此也是他们的效率，密切相关的这些几何方面。我们通过讨论两种具体情况来说明这些想法：一个缓慢驱动的量子比特不对称地耦合到两个保持在不同温度下的玻色子库，以及一个由旋转磁场驱动的量子点，并强烈耦合到具有不同极化的电子库。这两个例子都已经可以进行实验验证。
We present a general unified approach for the study of quantum thermal machines, including both heat engines and refrigerators, operating under periodic adiabatic driving and in contact with thermal reservoirs kept at different temperatures. We show that many observables characterizing this operating mode and the performance of the machine are of geometric nature. Heat-work conversion mechanisms and dissipation of energy can be described, respectively, by the antisymmetric and symmetric components of a thermal geometric tensor defined in the space of time-dependent parameters generalized to include the temperature bias. The antisymmetric component can be identified as a Berry curvature, while the symmetric component defines the metric of the manifold. We show that the operation of adiabatic thermal machines, and consequently also their efficiency, are intimately related to these geometric aspects. We illustrate these ideas by discussing two specific cases: a slowly driven qubit asymmetrically coupled to two bosonic reservoirs kept at different temperatures, and a quantum dot driven by a rotating magnetic field and strongly coupled to electron reservoirs with different polarizations. Both examples are already amenable for experimental verification.