中国物理B ›› 2016, Vol. 25 ›› Issue (10): 108506-108506.doi: 10.1088/1674-1056/25/10/108506

• INTERDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY • 上一篇    下一篇

Optical nuclear spin polarization in quantum dots

Ai-Xian Li(李爱仙), Su-Qing Duan(段素青), Wei Zhang(张伟)   

  1. Institute of Applied Physics and Computational Mathematics, Beijing 100088, China
  • 收稿日期:2016-04-18 修回日期:2016-06-05 出版日期:2016-10-05 发布日期:2016-10-05
  • 通讯作者: Ai-Xian Li, Wei Zhang E-mail:liaixian0123@sina.com;zhang_wei@iapcm.ac.cn
  • 基金资助:

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

Optical nuclear spin polarization in quantum dots

Ai-Xian Li(李爱仙), Su-Qing Duan(段素青), Wei Zhang(张伟)   

  1. Institute of Applied Physics and Computational Mathematics, Beijing 100088, China
  • Received:2016-04-18 Revised:2016-06-05 Online:2016-10-05 Published:2016-10-05
  • Contact: Ai-Xian Li, Wei Zhang E-mail:liaixian0123@sina.com;zhang_wei@iapcm.ac.cn
  • Supported by:

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

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.

关键词: nuclear spin polarization, coherent population trapping, electron dipole spin resonance

Abstract:

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.

Key words: nuclear spin polarization, coherent population trapping, electron dipole spin resonance

中图分类号:  (Magnetoelectronics; spintronics: devices exploiting spin polarized transport or integrated magnetic fields)

  • 85.75.-d
76.70.Fz (Double nuclear magnetic resonance (DNMR), dynamical nuclear polarization) 78.67.Hc (Quantum dots)