arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2102.04408cond-mat.mes-hall
收藏

相干性在基于量子点的库仑阻塞机器中的作用

Role of coherence in quantum-dot-based nanomachines within the Coulomb blockade regime

Federico D. Ribetto, Raúl A. Bustos-Marún, Hernan L. Calvo

摘要:

在过去的几十年中,库仑阻塞运输制度内的量子点已被提出作为各种纳米机器的基本构建模块。这包括热电设备,量子穿梭机,量子泵,甚至量子发动机。然而,在这种情况下,量子力学的作用通常仅限于提供能量量子化,而设备的工作原理最终与它们的经典对应物相同。在这里,我们研究基于量子点的纳米机器在库仑阻塞制度,但在配置中的点的状态的相干叠加起着至关重要的作用。我们表明,所研究的系统可以作为不同形式的“真正的”量子机器的基础,这些机器应该只在这些相干叠加的存在下工作。我们分析了这些机器对不同的非平衡源(偏置电压,温度梯度和外部驱动)的效率和限制它的因素,包括退相干和在绝热膨胀的电荷/热流中出现的不同顺序的作用。

英文摘要:

During the last decades, quantum dots within the Coulomb blockade regime of transport have been proposed as essential building blocks for a wide variety of nanomachines. This includes thermoelectric devices, quantum shuttles, quantum pumps, and even quantum motors. However, in this regime, the role of quantum mechanics is commonly limited to provide energy quantization while the working principle of the devices is ultimately the same as their classic counterparts. Here, we study quantum-dot-based nanomachines in the Coulomb blockade regime, but in a configuration where the coherent superpositions of the dots' states plays a crucial role. We show that the studied system can be used as the basis for different forms of "true" quantum machines that should only work in the presence of these coherent superpositions. We analyze the efficiency of these machines against different nonequilibrium sources (bias voltage, temperature gradient, and external driving) and the factors that limit it, including decoherence and the role of the different orders appearing in the adiabatic expansion of the charge/heat currents.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑