Self-Consistent Spin-Wave Approach to Quantum Spin Systems
Self-Consistent Spin-Wave Approach to Quantum Spin Systems
复制标题
量子自旋系统的自洽自旋波方法
DOI：
10.1143/jpsj.61.2909
复制
发表时间：
1992
影响因子：
1.7
通讯作者：
T. Aoki
中科院分区：
文献类型：
--
作者：
T. Aoki
利用运动方程方法研究了长程有序量子自旋系统的基态。自旋算符的运动方程通过引入有效场而线性化，有效场是序参量本身。线性化的运动方程和自旋算符的近似对易关系的使用导致系统的玻色子表示。强调了在具有沿着x轴的长程有序的基态中，关系式（Sj y）2 +（Sj z）2 =1/2应在平均值中保持。在玻色子近似下，利用上述自旋涨落约束，计算了长程有序和基态能量。计算结果与用不同方法得到的结果吻合较好。
On the basis of the method of equation of motion, the ground states of the quantum spin systems with a long-range order are studied. The equations of motion for the spin operators are linearized by introduction of the effective field, which is the order parameter itself. The linearized equations of motion and the use of approximate commutation relations for spin operators lead to the boson representation of the systems. It is emphasized that in the ground state with the long-range order along the x -axis, the relationship ( S j y ) 2 +( S j z ) 2 =1/2 should be retained in the average. By use of the above constraint for spin fluctuations, the values of the long-range order and ground-state energy are calculated within the boson approximation. The results agree well with ones obtained by different methods.