Gate-controlled guiding of electrons in graphene
Gate-controlled guiding of electrons in graphene
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DOI：
10.1038/nnano.2011.3
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发表时间：
2011-04-01
影响因子：
38.3
通讯作者：
Marcus, C. M.
中科院分区：
文献类型：
--
作者：
Williams, J. R.;Low, Tony;Marcus, C. M.
弹道半导体结构允许在电子系统中实现类似光学的现象，包括电子的磁聚焦（1）和静电透镜（2）。石墨烯独有的一个扩展是使用n和p载流子类型来创建具有正折射率和负折射率的光学器件的电子类似物（3）。在这里，我们使用石墨烯中p和n载流子类型的栅极控制密度来演示光纤引导的电子模拟（4-8）。研究了两种基本效应：双极p-n结引导，基于通过石墨烯和p-n结之间的界面的角度选择性传输的原理;以及单极光纤引导，使用由载流子密度控制的全内反射。我们还演示了调制的引导效率，通过门控，这些数据与数值模拟的比较表明，引导性能受到界面粗糙度的限制。石墨烯中p-n和光纤引导的发展可能导致高迁移率器件中的电可重构布线。
Ballistic semiconductor structures have allowed the realization of optics-like phenomena in electronic systems, including the magnetic focusing(1) and electrostatic lensing(2) of electrons. An extension that appears unique to graphene is to use both n and p carrier types to create electronic analogues of optical devices with both positive and negative indices of refraction(3). Here, we use the gate-controlled density of both p and n carrier types in graphene to demonstrate the electronic analogue of fibre-optic guiding(4-8). Two basic effects are investigated: bipolar p-n junction guiding, based on the principle of angle-selective transmission through the interface between the graphene and the p-n junction; and unipolar fibre-optic guiding, using total internal reflection controlled by carrier density. We also demonstrate modulation of the guiding efficiency through gating, and comparison of these data with numerical simulations indicates that guiding performance is limited by the roughness of the interface. The development of p-n and fibre-optic guiding in graphene may lead to electrically reconfigurable wiring in high-mobility devices.