阻挫磁性链中自旋流体二聚化相变点计算的一个有效方法

An effective approach to fluid-dimer critical point for frustrated antiferromagnetic Heisenberg chain

应用双时格林函数这一有效的方法,考虑自旋为S=1/2的海森堡反铁磁链中最近邻和次近邻的作用,通过使用简单的退耦近似——无规相近似,解析地计算得到了低维阻挫系统由自旋流体向二聚化转变的临界值为cα=0.242.计算方法简单,计算结果与其它理论结果一致.

An effective approach, the two time Green function method, is applied to analytically investigate the critical value ac of the fluid-dimer transition for the S = 1/2 frustrated antiferromagnetic Heisenberg chain, where the nearest neighbor and next neighbor interactions are considered. By using a simple decoupling scheme, the random phase approximation （RPA）, it is shown that the analytical result ac =0. 242 is in good agreement with the other theoretical estimates.