和隧穿量子点作用单模场压缩_毕业论文

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和隧穿量子点作用单模场压缩

摘要:本课题主要研究的是隧穿单模光场-不对称双量子点系统的光场压缩效应,这涉及到不对称双量子点、光腔和周围环境组成的系统,以及它们之间的相互作用。我们首先回顾了量子点最初的灵感来源——十字形金属丝中的束缚态,之后又引入本课题研究的由两个量子点组成的不对称双量子点模型,最后回顾了最近国内外关于不对称双量子点研究进展。在不考虑耗散的理想情况下,通过数值求解密度算符方程,我们详细研究了初始平均光子数、隧穿强度以及激光失谐量与场压缩的关系。在考虑激子衰减和退相时,通过求解刘维尔-冯诺依曼-林得布拉德方程,我们得出了衰减速率和退相速率对光场压缩的作用规律。考虑到光腔损耗无法避免的实际情况,最后我们通过数值求解系统主方程,详细研究了腔损耗率对光场压缩的影响,并且比较了含与不含不对称双量子点损耗腔中的光场演化;并且给出了一种导出只含场的腔中相干光场光子数分布时间演化解析表达式的新方法。

关键词:不对称双量子点;光场压缩;布居数

Abstract:This paper focuses on the light field squeezing effect of tunneling quantum dots-field system, which involves a quantum dot molecule and optical cavity and the surrounding environment. We first review the initial idea of quantum dots -- the bound state in the cross-shaped wire, and then introduce the quantum dot molecule model. Then, we review the recent progress of research on quantum dots, and the significance of this research. We study the influence of the initial average photon numbers, the tunneling strength and the laser detuning on the field squeezing by solving the density operator equation numerically without considering dissipation. In the consideration of the decay and dephasing of the excited quantum dot molecule, we obtain how the decay rate and the dephasing rate influence the squeezing of the light field by solving the Liouville-von Neumann-Lindblad equation numerically. Finally, considering the actual situation that the cavity dissipation can not be avoided, we study how cavity dissipative rate influence the squeezing of light field by solving the quantum master equation. And the evolution of the light field in the cavity with asymmetric double dots is compared with that without the double dots. And a new derivation for the time evolution analytical solution of the initial coherent light field is found in the dissipative cavity.

Keywords: quantum dot molecule; light squeezing; population

目录

第一章绪论 1

1.1研究背景 1

1.1.1量子点模型的理论探索 1

1.1.2不对称双量子点模型 2

1.1.3压缩光场的性质、产生及其广泛应用 3

1.1.4原子分子以及其他量子系统对光场压缩产生的影响 4

1.2隧穿耦合不对称双量子点模型研究现状 5

1.2.1隧穿不对称双量子点中的几何相位研究 5

1.2.2基于隧穿不对称双量子点的隧穿诱导透明 6

1.2.3弱耦合机制下隧穿不对称量子点的光学双稳态 7

第二章和隧穿不对称双量子点作用的单模场压缩 8

2.1模型建立 8

2.2初始平均光子数对场压缩的作用 11

2.3隧穿强度对场压缩的作用 13

2.4失谐量对场压缩的影响 (责任编辑:qin)