介观电路量子力学性质的研究

【作者】 金海兰；

【导师】 崔元顺；

【作者基本信息】 延边大学 ， 光学， 2007， 硕士

【摘要】 本文是在电荷离散化的基础上，运用已有的量子化理论，对不同介观电路模型的量子力学效应进行了相应的理论推导和数值分析，并做出进一步的研究。全文的主要内容共分为三章：第一章是引言部分，介绍了介观系统的相关知识和介观电路的研究进展。在第二章，首先，简述了非耗散介观电路的量子化方法，为本文后面的工作提供了所需的计算方法。然后，考虑到实际工作中总是存在着耗散，计算了相应的Fock态下、(?)的本征态下耗散介观电路的量子涨落，研究了影响量子涨落的因素。结果表明：量子涨落与介观系统固有参数、电荷量子化密切相关。第三章研究了介观金属双环互感耦合系统的库仑阻塞效应及量子涨落问题。库仑阻塞的条件与回路电参数有关，并且两回路中磁通的时间变化率同驱动源的取值存在一定的约束关系。在Fock态下外磁场对介观金属双环系统的量子涨落并不产生影响。我们认为，上述这些量子力学效应在其他的电路模型中也存在，值得我们深入研究。这对于设计微小电路、提高电路集成度、降低单片功耗、压低量子噪声具有一定的现实指导意义。更多还原

【Abstract】 In this paper, the theory deductions and numerical analysis on the quantummechanics effects for different models of mesoscopic circuits are studieddeeply under some special quantum states by using quantum theory and takingaccount of the charge discreteness.The thesis is divided into three chapters which are discribed as follows.Chapter 1 is the introduction of mesoscopic system which illustrates thefundamental concepts and recent development.In Chpater 2, Firstly, we summarized the method of quantization formesoscopic circuits which relevants to our later work. Secondly, cosideringthe resistance always exists in mesoscopic system actually, the quantumfluctuations in the mesoscopic circuits with dissipation are caculatedrespectively under Fock state and eigen state of ladder functor, and the effectsof the parameters on the quantum fluctuations are also investigated. Theresults show that the quantum fluctuations are related to the parameters of thecircuits and charge quantization closely.In Chapter 3, the effects of Coulomb blockade and quantum fluctuationsare investigated for the mutual inductances coupled mesoscopic system.Further, the relationships of quantum current and the conditions of Coulombblockade in this system are given here. The outcome indicates that theconditions of the Coulomb blockade are related to electric parameters of the loops, and the time variety frequency of the magnetic flux in two loops hassome connections with the value of the drive source expressly, The externalflux didn’t take any effects on quantum fluctuations in Fock state.These quantum mechanics effects will exist in other models, and we cantake more attentions onit. These work will bring some guiding significances ondesigning micro-circuit, improving circuit integration level, reducing themonolithic power dissipation and lowering quantum noise.更多还原