中国物理B ›› 2017, Vol. 26 ›› Issue (3): 37304-037304.doi: 10.1088/1674-1056/26/3/037304

• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇    下一篇

Photon-mediated spin-polarized current in a quantum dot under thermal bias

Feng Chi(迟锋), Liming Liu(刘黎明), Lianliang Sun(孙连亮)   

  1. 1 School of Electronic and Information Engineering, University of Electronic Science and Technology of China, Zhongshan Institute, Zhongshan 528400, China;
    2 College of Science, North China University of Technology, Beijing 100041, China
  • 收稿日期:2016-10-22 修回日期:2016-12-17 出版日期:2017-03-05 发布日期:2017-03-05
  • 通讯作者: Feng Chi E-mail:chifeng@semi.ac.cn
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 61274101 and 51362031), the Initial Project for High-Level Talents of UESTC, Zhongshan Insitute, China (Grant No. 415YKQ02), and China Postdoctoral Science Foundation (Grant No. 2014M562301).

Photon-mediated spin-polarized current in a quantum dot under thermal bias

Feng Chi(迟锋)1, Liming Liu(刘黎明)1, Lianliang Sun(孙连亮)2   

  1. 1 School of Electronic and Information Engineering, University of Electronic Science and Technology of China, Zhongshan Institute, Zhongshan 528400, China;
    2 College of Science, North China University of Technology, Beijing 100041, China
  • Received:2016-10-22 Revised:2016-12-17 Online:2017-03-05 Published:2017-03-05
  • Contact: Feng Chi E-mail:chifeng@semi.ac.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 61274101 and 51362031), the Initial Project for High-Level Talents of UESTC, Zhongshan Insitute, China (Grant No. 415YKQ02), and China Postdoctoral Science Foundation (Grant No. 2014M562301).

摘要: Spin-polarized current generated by thermal bias across a system composed of a quantum dot (QD) connected to metallic leads is studied in the presence of magnetic and photon fields. The current of a certain spin orientation vanishes when the dot level is aligned to the lead's chemical potential, resulting in a 100% spin-polarized current. The spin-resolved current also changes its sign at the two sides of the zero points. By tuning the system's parameters, spin-up and spin-down currents with equal strength may flow in opposite directions, which induces a pure spin current without the accompany of charge current. With the help of the thermal bias, both the strength and the direction of the spin-polarized current can be manipulated by tuning either the frequency or the intensity of the photon field, which is beyond the reach of the usual electric bias voltage.

关键词: quantum dot, spin-polarized current, thermal bias, photon field

Abstract: Spin-polarized current generated by thermal bias across a system composed of a quantum dot (QD) connected to metallic leads is studied in the presence of magnetic and photon fields. The current of a certain spin orientation vanishes when the dot level is aligned to the lead's chemical potential, resulting in a 100% spin-polarized current. The spin-resolved current also changes its sign at the two sides of the zero points. By tuning the system's parameters, spin-up and spin-down currents with equal strength may flow in opposite directions, which induces a pure spin current without the accompany of charge current. With the help of the thermal bias, both the strength and the direction of the spin-polarized current can be manipulated by tuning either the frequency or the intensity of the photon field, which is beyond the reach of the usual electric bias voltage.

Key words: quantum dot, spin-polarized current, thermal bias, photon field

中图分类号:  (Quantum dots)

  • 73.21.La
72.15.Jf (Thermoelectric and thermomagnetic effects) 73.50.Lw (Thermoelectric effects)