BN掺杂石墨烯纳米带电子输运第一性原理研究

发布时间：2018-01-05 22:08

本文关键词：BN掺杂石墨烯纳米带电子输运第一性原理研究　出处：《湖南大学》2015年硕士论文　论文类型：学位论文

【摘要】：近年来,随着科学技术的不断发展,越来越多的微电子器件和分子器件已经在实验和理论计算中被广泛研究,并且表现出与常规宏观体系不同的电子输运特性。这些年对于纳米结构、分子器件的开发和量子点的研究已经逐渐成为纳米材料研究的新趋势。其中,大量有趣的物理性质,例如:整流行为、负微分电阻和分子开关等现象,已经被广泛的研制并且进入分子器件实验室中进行研发和制造。基于非平衡格林函数方法结合密度泛函理论,研究了B,N,和两者顶点掺杂的三角形石墨烯纳米带的电子输运性质。研究发现,在BN顶点掺杂的情况下可以观察到显著的整流行为和明显的负微分电阻现象。这是因为在三角顶点掺杂形成一个类似PN结的现象,从而导致整流行为。此外,调节两个掺杂中间原子之间的距离可以有效调控其弱相互作用,并且随着它们之间距离的增加,整流行为和负微分电阻现象会出现削弱的趋势。根据计算结果可以认为,用BN顶点掺杂三角石墨烯纳米带实现准确调制整流现象为纳米分子器件的设计提供理论依据。考虑到之前的工作对掺杂的个数存在局限,但是在实际的分子器件设计会遇到掺杂个数增加和位置不同的情况,因此通过研究掺杂的个数和位置来提升整流效果并构建新的整流器件模型。基于非平衡格林函数方法结合密度泛函理论,又研究了在相同宽度情况下掺杂不同个数的BN及其不同排列组合情况下的电子输运性质。计算结果表明当宽度一定时,改变其掺杂的排列组合会出现一些很有趣的物理现象,如随着掺杂BN的个数的增多,其电子输运性质表新出独特的反向整流现象,并且随着掺杂个数的增多,反向整流效果越好。这些结果同样表明在一定程度上可以通过控制分子器件掺杂个数和位置来调控分子器件的电子输运性质。
[Abstract]:In recent years, with the development of science and technology, microelectronic devices and molecular devices has been more and more in the experimental and theoretical calculation are studied, and the show is different from the conventional system of macro electronic transport properties. These years for the nano molecular devices, research and the development of quantum dots has gradually become a new trend of research nano materials. Among them, a lot of interesting physical properties, for example: rectifying behavior, negative differential resistance and molecular switches and other phenomena, has been widely developed and development and manufacturing into molecular devices in the laboratory. The non-equilibrium Green function method based on density functional theory, the research of B, N, triangular graphene Nano Electronics with the transport properties and the two vertex doping. The study found that the peak of BN doping can be observed in the absence of significant rectifying behavior and obvious negative differential resistance The phenomenon. This is because of the formation of a similar phenomenon in the triangle vertices of PN junction doping, resulting in rectifying behavior. In addition, regulation between the two doped intermediate atomic distance can effectively control the weak interaction, and with the increase of the distance between them, rectifying behavior and negative differential resistance phenomenon will be calculated according to the weakening trend. It can be concluded that BN doping vertex triangle Shi Moxi nanobelts achieve accurate modulation rectification phenomenon provides a theoretical basis for the design of nano molecular devices. Considering previous work a number of doping limitations, but in the design of molecular devices will meet the actual number of different doping increase and position, so through the study of doping the number and position to improve the rectification effect and construct the new model of the rectifier device. The non-equilibrium Green function method based on density functional theory, and research. Electron doping different at the same width case number BN and different permutation and combination of case transport properties. The calculation results show that when a certain width, changing its doping combinations there will be some very interesting phenomena, such as the increase of the number of doped BN, the electronic transport properties of a new table reverse rectification of a unique phenomenon, and with the increase in the number of doping, the better reverse rectification effect. These results also show that the electron in a certain extent can be controlled by the number and position of doping molecular devices to control the transport properties of molecular devices.

【学位授予单位】：湖南大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB383.1;O613.71

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