中国物理B ›› 2003, Vol. 12 ›› Issue (8): 905-910.doi: 10.1088/1009-1963/12/8/316

• • 上一篇    下一篇

Bifurcation of a periodic instanton and quantum-classical transition in the biaxial nano-ferromagnet with a magnetic field along hard axis

严启伟1, 李志坚2, 聂一行3, 梁九卿4   

  1. (1)Institute of Physics, Chinese Academy of Sciences, Beijing 100080, China; (2)Institute of Theoretical Physics and Department of Physics, Shanxi University, Taiyuan 030006, China; (3)Institute of Theoretical Physics and Department of Physics, Shanxi University, Taiyuan 030006, China; Department of Physics, Yanbei Normal Institute, Datong 037000, China; (4)Institute of Theoretical Physics and Department of Physics, Shanxi University, Taiyuan 030006, China; Institute of Physics, Chinese Academy
  • 收稿日期:2002-11-27 修回日期:2002-12-22 出版日期:2003-08-16 发布日期:2005-03-16
  • 基金资助:
    Project supported by the National Nature Science Foundation of China (Grant Nos 10075032 and 10175039), the Shanxi Nature Science Foundation (Grant No 2001007), and by the Fund of Chinese Academy of Sciences entitled "Nanomic Science and Technology".

Bifurcation of a periodic instanton and quantum-classical transition in the biaxial nano-ferromagnet with a magnetic field along hard axis

Nie Yi-Hang (聂一行)ab, Li Zhi-Jian (李志坚)a, Liang Jiu-Qing (梁九卿)ac, Yan Qi-Wei (严启伟)c   

  1. a Institute of Theoretical Physics and Department of Physics, Shanxi University, Taiyuan 030006, China; b Department of Physics, Yanbei Normal Institute, Datong 037000, China; c Institute of Physics, Chinese Academy of Sciences, Beijing 100080, China
  • Received:2002-11-27 Revised:2002-12-22 Online:2003-08-16 Published:2005-03-16
  • Supported by:
    Project supported by the National Nature Science Foundation of China (Grant Nos 10075032 and 10175039), the Shanxi Nature Science Foundation (Grant No 2001007), and by the Fund of Chinese Academy of Sciences entitled "Nanomic Science and Technology".

摘要: Crossover from classical to quantum regimes of the barrier transition rate in a biaxial ferromagnetic magnet with a magnetic field applied along hard anisotropy axis is investigated. We show that the type of action-temperature diagrams can be determined by counting the number of bifurcation points. The model possesses not only the known type I and II, but also the interesting type III and IV of transition which do not occur in general.

Abstract: Crossover from classical to quantum regimes of the barrier transition rate in a biaxial ferromagnetic magnet with a magnetic field applied along hard anisotropy axis is investigated. We show that the type of action-temperature diagrams can be determined by counting the number of bifurcation points. The model possesses not only the known type I and II, but also the interesting type III and IV of transition which do not occur in general.

Key words: quantum tunnelling, phase transition

中图分类号:  (Magnetic phase boundaries (including classical and quantum magnetic transitions, metamagnetism, etc.))

  • 75.30.Kz
75.30.Gw (Magnetic anisotropy) 73.23.-b (Electronic transport in mesoscopic systems)