论文标题
通过多末端单层石墨烯设备效应可调谷选择
Effectuating tunable valley selection via multi-terminal monolayer graphene devices
论文作者
论文摘要
使用二维材料的valleytronics为信息处理提供了前所未有的机会，而山谷偏光层是基本的构建基础。诸如应变工程范式，纳入线缺陷以及用于创建山谷极化的广泛探索的静电磁场的应用遭受了较小的传输或缺乏极化方向性的限制。 We propose an all-electrical valley polarizer using zigzag edge graphene nanoribbons in a multi-terminal device geometry, that can be gate-tuned to operate along two independent regimes: (i) terminal-specific valley filter that utilizes bandstructure engineering, and (ii) parity-specific valley filter that exploits the parity selection rule in zigzag edge graphene.我们表明，该设备在影响山谷极化的多模式操作方面表现出有趣的物理，因此研究了影响宽器械几何形状极化的各种因素，例如，石墨烯迪拉克·费米斯（Dirac Fermions）的光学类似物，通过p-n连接的角度选择性传播以及边缘状态的定位。我们优化了所提出的设备的几何形状，以实现最大的谷地极化，从而铺平了使用单层石墨烯迈向基于物理的可调式valleytronic设备设计。
Valleytronics using two-dimensional materials opens unprecedented opportunities for information processing with the valley polarizer being a basic building block. Paradigms such as strain engineering, the inclusion of line defects, and the application of electrostatic-magnetic fields extensively explored for creating valley polarization suffer from limitations like smaller transmission or the lack of polarization directionality. We propose an all-electrical valley polarizer using zigzag edge graphene nanoribbons in a multi-terminal device geometry, that can be gate-tuned to operate along two independent regimes: (i) terminal-specific valley filter that utilizes bandstructure engineering, and (ii) parity-specific valley filter that exploits the parity selection rule in zigzag edge graphene. We show that the device exhibits intriguing physics in the multimode regime of operation that affects the valley polarization and hence investigate various factors affecting the polarization in wide device geometries, such as, optical analogs of graphene Dirac fermions, angle-selective transmission via p-n junctions, and the localization of edge states. We optimize the geometry of the proposed device to achieve maximum valley polarization, thereby, paving the way toward a physics based tunable valleytronic device design using monolayer graphene.
