以Floquet理論分析奈米尺度系統的電子傳輸

A Generalized Floquet Theory for the Treatment of Electron Transport of Nanoscale Systems

洪士涵(Shih-Han Hung)

指導教授 ： 朱時宜

國立臺灣大學/理學院/物理研究所/碩士(2009年)

https://doi.org/10.6342/NTU.2009.01725

摘要

奈米尺度系統的電子傳輸常假設於寬帶極限之下，在此極限下，記憶效應會隨之忽略。在此論文中，我們將Floquet理論應用於奈米尺度系統之電子傳輸，探討在時變外加場之下記憶效應的多光子同調穿隧截止效應。以電極─雙量子點─電極系統為例，電極與量子點之交互作用假設為勞侖茲分佈函數時，探討記憶效應之影響以及多光子同調穿隧截止效應之物理機制。

關鍵字

奈米尺度系統 ； 電子傳輸 ； 量子點 ； 記憶效應 ； 同調穿隧截止

並列摘要

Electron transport through nanoscale systems are often studied in the wide-band limit without taking the memory effect into consideration. In this thesis, we present a novel Floquet approach in electron transport through nanoscale systems beyond the wide-band limit to explore the multi-photon (MP) coherent destruction of tunneling (CDT) with memory effect in the presence of time-dependent driving field. As a case study, the time-averaged current is calculated in an electrode-double quantum dots-electrode system driven by a periodic field using single Lorentzian spectral density function and a detailed analysis is presented to illustrate the origin of MP-CDT as well as the significance of memory effect.

並列關鍵字

nanoscale system ； electron transport ； quantum dot ； memory effect ； coherent destruction of tunneling

參考文獻

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