中国物理B ›› 2011, Vol. 20 ›› Issue (12): 127203-127203.doi: 10.1088/1674-1056/20/12/127203

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Persistent current in a magnetized Rashba ring

汪军1, 张林2   

  1. (1)Department of Physics, Southeast University, Nanjing 210096, China; (2)Department of Physics, Southeast University, Nanjing 210096, China;Department of Applied Physics, College of Science, Nanjing Forestry University, Nanjing 210037, China
  • 收稿日期:2011-04-06 修回日期:2011-08-08 出版日期:2011-12-15 发布日期:2011-12-15
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 110704032 and 110704033), the Natural Science Foundation of Jiangsu Province of China (Grant No. BK2010416), and the National Basic Research Development Program of China (Grant No. 2009CB945504).

Persistent current in a magnetized Rashba ring

Zhang Lin(张林)a)b)† and Wang Jun(汪军)a)‡   

  1. a Department of Physics, Southeast University, Nanjing 210096, China; b Department of Applied Physics, College of Science, Nanjing Forestry University, Nanjing 210037, China
  • Received:2011-04-06 Revised:2011-08-08 Online:2011-12-15 Published:2011-12-15
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 110704032 and 110704033), the Natural Science Foundation of Jiangsu Province of China (Grant No. BK2010416), and the National Basic Research Development Program of China (Grant No. 2009CB945504).

摘要: We theoretically study the persistent currents flowing in a Rashba quantum ring subjected to the Rashba spin-orbit interaction. By introducing uniform or nonuniform magnetization into the ring, we find that a nonzero persistent charge current circulates in the ring, which stems from the original equilibrium spin current due to the Rashba spin-orbit interaction. Because of broken time reversal symmetry, the two oppositely flowing spin-up and spin-down charge currents of the equilibrium spin current are no longer equal, and so a net persistent charge current can flow in the system. It is also found that the persistent current can be modulated by the Fermi energy, the Rashba spin-orbit interaction strength and the magnetization in the ring. Moreover, the magnetization perpendicular to the ring plane can optimize the current. The persistent current flowing in the ring is a manifestation of the nonzero equilibrium spin current existing in the ring.

关键词: persistent current, equilibrium spin current, Rashba ring, magnetization

Abstract: We theoretically study the persistent currents flowing in a Rashba quantum ring subjected to the Rashba spin-orbit interaction. By introducing uniform or nonuniform magnetization into the ring, we find that a nonzero persistent charge current circulates in the ring, which stems from the original equilibrium spin current due to the Rashba spin-orbit interaction. Because of broken time reversal symmetry, the two oppositely flowing spin-up and spin-down charge currents of the equilibrium spin current are no longer equal, and so a net persistent charge current can flow in the system. It is also found that the persistent current can be modulated by the Fermi energy, the Rashba spin-orbit interaction strength and the magnetization in the ring. Moreover, the magnetization perpendicular to the ring plane can optimize the current. The persistent current flowing in the ring is a manifestation of the nonzero equilibrium spin current existing in the ring.

Key words: persistent current, equilibrium spin current, Rashba ring, magnetization

中图分类号:  (Spin polarized transport in semiconductors)

  • 72.25.Dc
72.25.Mk (Spin transport through interfaces) 73.23.Ra (Persistent currents)