论文标题
描述可变磁场中两个耦合旋转的新方法
New approach to describe two coupled spins in a variable magnetic field
论文作者
论文摘要
我们提出了一种描述在外部时间依赖性磁场中与超精细相互作用结合的两种旋转的演变的方法。我们将方法应用于与轴向对称性相互作用的情况下，可以精确地以恒定，适当定向的磁场求解。为了治疗非组织动态问题，我们通过更改表示形式来修改时间依赖性的schrödinger方程，通过利用瞬时（绝热）基础，这些方程在任何时候都会使时间依赖的汉密尔顿对角线。报道了以透明的指数前系数的时间顺序有序指数的形式，转化的时间依赖性schrödinger的解。当绝热变化的磁场消散系统时，该解决方案被高度简化。这里提出的方法可用于对其他动态问题的扰动处理，而无需确切的解决方案。
We propose a method to describe the evolution of two spins coupled by hyperfine interaction in an external time-dependent magnetic field. We apply the approach to the case of hyperfine interaction with axial symmetry, which can be solved exactly in a constant, appropriately oriented magnetic field. In order to treat the nonstationary dynamical problem, we modify the time-dependent Schrödinger equation through a change of representation that, by exploiting an instantaneous (adiabatic) basis makes the time-dependent Hamiltonian diagonal at any time instant. The solution of the transformed time-dependent Schrödinger in the form of chronologically ordered exponents with transparent pre-exponential coefficients is reported. This solution is highly simplified when an adiabatically varying magnetic field perturbs the system. The approach here proposed may be used for the perturbative treatment of other dynamical problems with no exact solution.
