Optical nuclear spin polarization in quantum dots

作     者：李爱仙 段素青 张伟 

作者机构：Institute of Applied Physics and Computational Mathematics 

出 版 物：《Chinese Physics B》 (中国物理B（英文版）)

年 卷 期：2016年第25卷第10期

页      面：535-539页

核心收录：

学科分类：080903[工学-微电子学与固体电子学] 0809[工学-电子科学与技术（可授工学、理学学位）] 07[理学] 070205[理学-凝聚态物理] 08[工学] 080501[工学-材料物理与化学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0702[理学-物理学] 

基　　金：partially supported by the National Natural Science Foundations of China(Grant Nos.11374039 and 11174042) the National Basic Research Program of China(Grant Nos.2011CB922204 and 2013CB632805) 

主　　题：nuclear spin polarization coherent population trapping electron dipole spin resonance 

摘      要：Hyperfine interaction between electron spin and randomly oriented nuclear spins is a key issue of electron coherence for quantum information/computation. We propose an efficient way to establish high polarization of nuclear spins and reduce the intrinsic nuclear spin fluctuations. Here, we polarize the nuclear spins in semiconductor quantum dot(QD) by the coherent population trapping(CPT) and the electric dipole spin resonance(EDSR) induced by optical fields and ac electric fields. By tuning the optical fields, we can obtain a powerful cooling background based on CPT for nuclear spin polarization. The EDSR can enhance the spin flip–flop rate which may increase the cooling efficiency. With the help of CPT and EDSR, an enhancement of 1300 times of the electron coherence time can be obtained after a 10-ns preparation time.