在寬-窄-寬量子元件之時變性傳輸

Abstract

我們考慮一偏壓跨接在源極和汲極間被分離閘極定義的準一維量子通道。有限偏壓和有限溫度效應將被納入考慮。為了研究時變傳輸的特性，我們考慮分離閘極上外加一頂閘極，用以提供具週期性時變的位能。在導引和窄通道間的非緩變模態混合特性將被討論。 在這個工作裡，我們分析模態混合效應造成的子帶間躍遷和週期性時變位能造成的邊帶間躍遷。光輔助和光壓抑的特性都可以在電導對入射電子能量的函數中發現。除此之外，我們考慮了有限溫度和偏壓效應，用以研究非線性量子傳輸和熱擴張性質。

We consider a semiconductor quantum device that is transversely confined by a pair of split-gate forming a quasi-one-dimensional narrow channel and is biased by the source and drain electrodes. Both the finite-bias and the finite-temperature effects are explicitly included in our calculation. In order to investigate the time-dependent transport behavior, we consider a top-gate in front of the split-gate for generating time-periodic potential. The nonadiabatic mode-mixing features between the narrow channel and the leads are included in the calculation. In this work, we have analyzed the quantum transport properties involving the inter-subband transitions due to the mode-mixing effects and the inter-sideband transitions due to the time-periodic potential. Both the photon-assisted and the photon-suppressed features can be found in conductance as a funtion of the incident electron energy. Moreover, we explicitly include the finite-bias and finite-temperaure effects to investigate the nonlinear quantum transport and thermal broadening properties.