论文标题
小型杂环分子作为多晶晶体管:量子多体方法
Small Heterocyclic Molecule as Multistate Transistor: A Quantum Many-body Approach
论文作者
论文摘要
弱耦合的分子连接是一个活跃而重要的研究领域,因为它们表现出各种非线性转运现象。我们已经使用量子多体方法与动力学(主)方程式的量子多体方法研究了载流子传输。有趣的是,已经获得了多种类型的非线性电流 - 电流特性,例如负差分电导(NDC),矫正,库仑楼梯,这是多层运输设备的标志。源水电压电压诱导的低洼多体状态的占用概率变化,这些状态在自然界对载体运输本质上不同,直接控制流经分子连接的净电流。我们进一步研究了通过该分子桥上载流子流的各种扰动(例如栅极电压和垂直磁场)的影响。有趣的是,我们发现,取决于应用扰动场的强度,几种现象,例如关闭电流,对NDC的抑制出现在设备中。从根本上讲,这种应用的扰动会修饰现场电荷密度以及运输活性通道的占用概率,从而导致该分子连接的转运行为发生显着改变。
Weakly coupled molecular junctions are an active and important field of research as they exhibit various non-linear transport phenomena. We have investigated the carrier transport through weakly coupled B2C2N2H6 molecules using quantum many-body approach coupled with kinetic (master) equations. Interestingly, various types of non-linear current-voltage characteristics, such as, negative differential conductance (NDC), rectifications, Coulomb staircase, which is the hallmark of multistate transport devices, have been obtained. The source-drain voltage induced change in the occupation probabilities of low-lying many-body states which are different in nature towards carrier transport, directly control the net current flowing through the molecular junctions. We further investigate the effect of different kinds of perturbations such as gate voltage and perpendicular magnetic field, over carrier-flow through this molecular bridge. Interestingly, we find that depending on the strength of the applied perturbating field, several phenomena, such as switching off of current, suppression of NDC appears in the devices. Fundamentally, this applied perturbations modifies both the site charge density as well as occupation probabilities of transport active channels, resulting in a significant alteration in transport behavior of this molecular junction.