论文标题
基于库仑耦合系统的现实非本地热发动机
A realistic non-local heat engine based on Coulomb coupled systems
论文作者
论文摘要
基于库仑耦合系统的最佳非本地热发动机,要求在量子点基底状态周围的能量解决系统之间耦合的能量解决的系统之间急剧变化。在现实的情况下,无法实现系统到保存的耦合中这种尖锐的阶梯式过渡。在这里,我建议基于库仑耦合系统的非本地热发动机的现实设计,该设计规定了对系统之间对库库耦合的任何变化的需求,这是文献中讨论的最佳设置所要求的。我证明,在相邻隧道耦合量子点之间的基态构型中,有意引入的不对称性(或能量差)与库仑偶联结合,足以将其从非局部热源转化为热电流的定向热流动的随机波动。然后,理论上使用量子标准方程(QME)方法对拟议的热发动机的性能以及所提出的热发动机进行了操作。已经证明,提议的设置的理论最大功率输出限于最佳设计的$ 50 \%$。尽管与最佳设置相比性能较低,但提出的设计的新颖性在于制造简单性以及合理的功率输出的结合。最后,分析了导致拟议设置性能恶化的顺序传输过程,并讨论了一种减轻此类运输过程的方法。本文提出的设置可用于设计和制造高性能的非本地低温热发动机。
Optimal non-local heat-engines, based on Coulomb-coupled systems, demand a sharp step-like change in the energy resolved system-to-reservoir coupling around the ground state of quantum-dots. Such a sharp step-like transition in the system-to-reservoir coupling cannot be achieved in a realistic scenario. Here, I propose realistic design for non-local heat engine based on Coulomb-coupled system, which circumvents the need for any change in the system-to-reservoir coupling, demanded by the optimal set-ups discussed in literature. I demonstrate that an intentionally introduced asymmetry (or energy difference) in the ground state configuration between adjacent tunnel coupled quantum dots, in conjugation with Coulomb coupling, is sufficient to convert the stochastic fluctuations from a non-local heat source into a directed flow of thermoelectric current. The performance, along with the regime of operation, of the proposed heat engine is then theoretically investigated using quantum-master-equation (QME) approach. It is demonstrated that the theoretical maximum power output for the proposed set-up is limited to about $50\%$ of the optimal design. Despite a lower performance compared to the optimal set-up, the novelty of the proposed design lies in the conjunction of fabrication simplicity along with reasonable power output. At the end, the sequential transport processes leading to a performance deterioration of the proposed set-up are analyzed and a method to alleviate such transport processes is discussed. The set-up proposed in this paper can be used to design and fabricate high-performance non-local cryogenic heat engines.