量子点输运电流的含频噪声谱的研究

项目名称： 量子点输运电流的含频噪声谱的研究

项目编号： No.11274085

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 数理科学和化学

项目作者： 金锦双

作者单位： 杭州师范大学

项目金额： 78万元

中文摘要： 电流噪声谱是由于电荷的离散性引起的电流涨落，所反映的信息远远多于电流或者电导，因而引起广泛的实验与理论的研究。现有理论的研究大多局限于零频（或者低频）噪声或者弱耦合下的最低价微扰展开处理，难以描述非马尔可夫效应与多电子协同遂穿效应所导致的动力学行为。本项目的主要研究内容是发展能描述多电子协同遂穿以及非马尔可夫效应的含频噪声谱方法，并在电流噪声谱水平上研究各种量子点的输运性质和动力学行为。理论的发展将基于我们近年来发展的严格、非微扰的非平衡输运理论：级联量子主方程方法以及具有可以解析分析处理的自洽－波恩近似下的量子主方程方法。首先建立条件量子主方程，结合MacDonald公式，发展有效计算电流噪声谱理论。其次在应用上开展对有电子关联和量子相干效应的各种量子点做深入的全方位的电流噪声谱研究。揭示多体库仑作用和量子相干特性，特别是非平衡Kondo效应和自旋相关输运的动力学行为特征。

中文关键词： 电流噪声谱；量子点；非平衡量子输运；量子动力学；量子主方程

英文摘要： Shot noise is a consequence of the quantization of charge. It provides additional information on a system which is not available through current or conductance measurements. It is thus has attracted a great amount of interest both in experimental and theoretical researches. However, most studies have been largely restricted to the zero (low)-frequency shot noise of the current fluctuations and/or lowest-order perturbation treatment for weak system-reservoir coupling. It can not describe the dynamical behavior of the combined effects of non-Markovian and cotunneling processes. In this project, we will present such a study. Based on our recently established exact,nonperturbative quantum transport theory and the self-consistent born approximation master equation approach, we will first construct the corresponding partical-number resolved master equation (also called conditional master eqaution). Together with MacDonald's formula, we will establish an efficient approach for the calculation of frequency-dependent noise spectrum, which can describe the combined effects of non-Markovian and cotunneling processes. We then carry out its applications for the current transport through variety quantum dots. We expect that new insight on the Coulomb interaction and quantum coherence will be extracted from the noise spectrum,

英文关键词： current noise spectra；quantum dot；nonequilibrium quantum transport；quantum dynamics；quantum master equation