大学物理 ›› 2011, Vol. 30 ›› Issue (7): 9-9.

• 著者文摘 • 上一篇    下一篇

含时磁共振系统的精确解和绝热近似解

张新琴 夏秀文 罗小兵   

  1. 井冈山大学数理学院,江西吉安343009
  • 出版日期:2011-07-25 发布日期:2011-07-20

Exact solution for a time-dependent magnetic resonance system and its quantum adiabatic approximation

  • Online:2011-07-25 Published:2011-07-20

摘要: 在瞬时本征态完备基矢下,把一个经典含时磁共振系统的薛定谔方程转化为二阶常系数微分方程,实现了该量子系统的精确求解.利用该系统的精确解,讨论了绝热近似的精确程度,非常清晰地刻画了绝热近似解和精确解在量子态分布概率上的差异.结果表明,若系统初态制备于某个瞬时本征态上,系统保持在该瞬时本征态的概率介于0.888 9~1之间,量子态间的跃迁概率介于0~0.111 1之间;且量子态分布概率受旋转磁场参数θ调制,当θ=0.304 3π时,跃迁概率达到最大.

关键词: 磁共振, 量子绝热定理, 瞬时本征态

Abstract: By taking instantaneous eigenstates as complete base vectors,a traditional time-dependent magnetic Schrodinger equation is transformed into a second-order differential equation with constant coefficient which can be solved exactly.The difference between accurate solution and adiabatic solution of the magnetic resonance system is studied,our results show that the tunneling rate can not be always ignored.When the rotating magnetic field adjustable parameter θ is equal to 0.304 3π,the tunneling rate can be increased to the maximum value of 0.111 1.

Key words: magnetic resonance, quantum adiabatic theorem, instantaneous eigenstate

中图分类号: 

  • O413.1