【摘要】 用代数动力学方法,研究旋转磁场中海森伯自旋链的几何相位.选用一个有部分各向异性海森伯耦合的3自旋12粒子环链系统.发现系统的哈密顿量具有su(2)代数结构.通过选择一个最佳规范变换,运用代数动力学方法得到系统的精确解.计算了系统的非绝热和绝热几何相位.把部分各向异性海森伯耦合推广到一般情况下的海森伯耦合,发现:在绝热近似下,海森伯耦合强度不影响系统的几何相位.更多还原

【Abstract】 The algebriaic dynamics is applied to investigate the geometric phase of a Heisenberg-chain in a rotating magnetic field.It is a su(2) algebraically symmetric 3-spin12 system with partially anisotropic coupling.The exact analytical solution of the time dependent Schrdinger equation and the geometric phases of this system are obtained in terms of gauge transformation and algebriaic dynamics.The partially anisotropic coupling is then extended to a more general coupling and the adiabatic geometric phases of the extended system are calculated.We find that the coupling strengths have no impact on the adiabatic geometric phases of the system.更多还原