Dynamics of the spin-1/2 isotropic XY chain in a transverse field
Dynamics of the spin-1/2 isotropic XY chain in a transverse field
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DOI：
10.1088/0305-4470/33/16/301
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发表时间：
2000-04-28
期刊：
影响因子：
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通讯作者：
Stolze, J
中科院分区：
文献类型：
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作者：
Derzhko, O;Krokhmalskii, T;Stolze, J
各向同性自旋 1/2 XY 链的动态 xx 和 xy 自旋对相关函数是在有限温度下存在横向 (z) 磁场的情况下对长开链进行数值计算的。从这些数据中，获得了动态结构因子 S-xx(kappa, omega) 和 S-xy(kappa, omega) 的第一个数值结果，并将其与 S-zz(kappa, omega) 的已知结果进行比较。虽然 S-zz(kappa, omega) 仅限于 (kappa, omega) 平面中的某些区域，但 S-xx(kappa, omega) 和 S-xy(kappa, omega) 则不然。然而，数值结果表明，后者的结构因子在 S-zz(kappa, omega) 定义的区域之外相当小，而且，它们在许多情况下，特别是在低温下，可以近似地由少量加宽的激发分支来描述。
Dynamic xx and xy spin pair correlation functions for the isotropic spin-1/2 XY chain are calculated numerically for long open chains in the presence of a transverse (z) magnetic field at finite temperature. From these data the first numerical results for the dynamic structure factors S-xx(kappa, omega) and S-xy(kappa, omega) are obtained and compared with the known results for S-zz(kappa, omega). While S-zz(kappa, omega) is restricted to certain regions in the (kappa, omega)-plane S-xx(kappa, omega) and S-xy(kappa, omega) are not. Nevertheless, the numerical results show that the latter structure factors are quite small outside the regions defined by S-zz(kappa, omega) and moreover, that they may in many circumstances, especially at low temperature, be approximately described by a small number of broadened excitation branches.