Suntornwipat Nattakarn, Majdi Saman, Gabrysch Markus, Kovi Kiran Kumar, Djurberg Viktor, Friel Ian, Twitchen Daniel J, Isberg Jan
Division for Electricity, Department of Electrical Engineering, Uppsala University, Box 65, 751 03, Uppsala, Sweden.
Center for Nanoscale Materials, Argonne National Laboratory, Argonne, Illinois 60439, United States.
Nano Lett. 2021 Jan 13;21(1):868-874. doi: 10.1021/acs.nanolett.0c04712. Epub 2020 Dec 18.
The valley degree of freedom in many-valley semiconductors provides a new paradigm for storing and processing information in valleytronic and quantum-computing applications. Achieving practical devices requires all-electric control of long-lived valley-polarized states, without the use of strong external magnetic fields. Because of the extreme strength of the carbon-carbon bond, diamond possesses exceptionally stable valley states that provide a useful platform for valleytronic devices. Using ultrapure single-crystalline diamond, we demonstrate electrostatic control of valley currents in a dual-gate field-effect transistor, where the electrons are generated with a short ultraviolet pulse. The charge current and the valley current measured at the receiving electrodes are controlled separately by varying the gate voltages. We propose a model to interpret experimental data, based on drift-diffusion equations coupled through rate terms, with the rates computed by microscopic Monte Carlo simulations. As an application, we demonstrate valley-current charge-state modulation of nitrogen-vacancy centers.
多能谷半导体中的谷自由度为谷电子学和量子计算应用中的信息存储与处理提供了一种新范式。要实现实际应用的器件，需要在不使用强外部磁场的情况下，对长寿命谷极化态进行全电控制。由于碳 - 碳键的极强强度，金刚石具有异常稳定的谷态，这为谷电子器件提供了一个有用的平台。我们使用超纯单晶金刚石，在双栅场效应晶体管中演示了谷电流的静电控制，其中电子由短紫外脉冲产生。通过改变栅极电压，可以分别控制在接收电极处测量的电荷电流和谷电流。我们提出了一个基于通过速率项耦合的漂移 - 扩散方程的模型来解释实验数据，其中速率由微观蒙特卡罗模拟计算得出。作为一个应用，我们展示了氮空位中心的谷电流电荷态调制。
