物理学报Issue(7)：1-9,9.DOI:10.7498/aps.64.077301
电子-声子相互作用对平行双量子点体系热电效应的影响
Influences of electron-phonon interaction on the thermoelectric effect in a parallel double quantum dot system
摘要
Abstract
A quantum-dot system is a typical low-dimensional system, and previous researches showed that its thermoelectric conversion efficiency can be markedy improved due to its unique physical properties. In this poper, we choose the parallel double-quantum-dot structure and discuss the influence of the electron-phonon interaction on the thermoelectric-related parameters, i.e., the electric conductance, thermopower, the figure of merit, and thermal conductance, by using the nonequilibrium Green’s function method. Our theoretical calculation results show that under the condition of low temperature, the occurrence of the Fano interference can assist to enhance the thermoelectric effect. When the electron-phonon interaction is taken into account, it can suppress the electric and thermal conductances to a certain extent because of its negative effect on the Fano interterence. However, we readily find that apparently the strengthening of the electron-phonon interaction cannot suppress the maximum of the thermopower. Instead, in some regions, the thermopower has an opportunity to enhance due to the appearance of a new channel caused by the electron-phonon interaction. Meanwhile, the figure of merit is found to cause similar effects to the thermopower. Therefore, in the case of low temperature, the electron-phonon interaction contributes little to the destruction of the thermoelectric effect, namely, it is not the necessary condition for the suppression of the thermoelectric effect. With the increase of temperature, the negative effect of the electron-phonon interaction on the Fano interference becomes relatively distinct, which inevitably weakens the thermoelectric effect. Results of this paper will help to clarify the influence of electron-phonon interaction on the thermoelectric effect.关键词
量子点/电子-声子相互作用/法诺效应/热电效应Key words
quantum dot/electron-phonon interaction/fano effect/thermoelectric effect引用本文复制引用
吴海娜,孙雪,公卫江,易光宇..电子-声子相互作用对平行双量子点体系热电效应的影响[J].物理学报,2015,(7):1-9,9.基金项目
中央高校基本科研业务费专项资金(批准号：N130505001)和辽宁省教育厅科学研究一般项目(批准号：L2014099)资助的课题 （批准号：N130505001）
