主讲人：赵新宇 副教授（福州大学）

题目：Measurement of Tunnel Coupling in a Si Double Quantum Dot Based on Charge Sensing

时间：2022年12月19日下午14:30

会议ID：（腾讯会议）825-745-004

联系人：吴威

报告摘要：

In Si quantum dots, the valley degree of freedom, in particular the generally small valley splitting and the dot-dependent valley-orbit phase, adds complexities to the low-energy electron dynamics. In particular, tunnel coupling, a key knob in charge and spin qubit manipulations, is strongly dependent on the valleyorbit coupling in a Si double dot. Here we propose a four-level model that incorporates excited valley states to extract ground-state tunnel coupling information for a Si double quantum dot. This scheme is based on a charge-sensing measurement on a double dot in equilibrium, as proposed in the widely used protocol for a GaAs double dot [DiCarlo et al., Phys. Rev. Lett. 92, 226801 (2004)]. Our theory helps determine both intra- and intervalley tunnel coupling with high accuracy, and is robust against uncertainties in system parameters such as valley splittings in the individual quantum dots.

Reference: Xinyu Zhao and Xuedong Hu, Phys. Rev. Applied 17, 064043  (2022)

个人简介：

赵新宇，福州大学物理系副教授。2009年硕士毕业于大连理工大学，2014年博士毕业于Stevens Institute of Technology, 2014-2020年在University at Buffalo, SUNY从事博士后研究。主要研究方向为非马尔可夫开系统动力学与半导体量子计算。目前已在Phys. Rev. A等国际知名期刊发表学术论文20余篇。