Department of Materials Science and Engineering, Drexel University, Philadelphia, Pennsylvania 19104 USA.
Phys Rev Lett. 2011 Oct 7;107(15):156802. doi: 10.1103/PhysRevLett.107.156802. Epub 2011 Oct 5.
We report the hot photoexcited electron transfer across the coaxial interface of a cylindrical core-shell nanowire. Modulation of the transfer rates, manifested as a large tunability of the voltage onset of negative differential resistance and of voltage-current phase, is achieved using three different modes. The coupling of electrostatic gating, incident photon energy, and the incident photon intensity to transfer rates is facilitated by the combined influences of geometric confinement and heterojunction shape on hot-electron transfer, and by electron-electron scattering rates that can be altered by varying the incident photon flux, with evidence of weak electron-phonon scattering. Dynamic manipulation of this transfer rate permits the introduction and control of a continuously adjustable phase delay of up to ∼130° within a single nanometer-scale device element.
我们报告了在圆柱形核壳纳米线的同轴界面上的热光激发电子转移。通过三种不同模式实现了转移速率的调制，表现为负微分电阻的电压起始和电压-电流相位的大可调性。静电门控、入射光子能量和入射光子强度对转移速率的耦合是由几何限制和异质结形状对热电子转移的综合影响以及通过改变入射光子通量来改变电子-电子散射率来实现的，并且存在弱电子-声子散射的证据。这种转移速率的动态控制允许在单个纳米级器件元件中引入和控制高达约 130°的连续可调相位延迟。
