论文标题
在磁场中的方格上的抗铁磁旋转1/2海森堡模型的光谱特征
Spectral characteristics of the antiferromagnetic spin-1/2 Heisenberg model on the square lattice in a magnetic field
论文作者
论文摘要
我们预测，横向磁场（H）中有序的正方形量子抗铁磁铁中的自旋波可以证明三种旋转激发模式。从自洽旋转不变的绿色函数方法开始，以H构建了一个新的平均场理论。该方法保留了翻译和轴向对称性，并为这三种模式中的每种模式提供了单点约束的精确满足。我们检查了动态结构因子S（aa）（k，w），a = x，y，z。据表明，由于在A，B旋转旋转绿色的功能上出现了非辅助性，因此H的引入H导致了两种退化自旋模式的杂交。该理论与确切的对角研究的比较以及对非弹性中子散射实验的结果进行了讨论。我们还讨论了该理论与现有理论的对应关系，该理论仅允许对总S（K，W）的两种旋转激发模式（K）。
We predict that spin-waves in an ordered square quantum antiferromagnet in a transverse magnetic field (h) may demonstrate three modes of spin excitations. Starting from the self-consistent rotation-invariant Green's function method, a new mean-field theory is constructed for h not equal to 0. The method preserves the translational and the axial symmetries, and provides exact fulfillment of the single-site constraint for each of the three modes. We examine the dynamical structure factors S(aa)(k,w), a= x, y, z. It is shown, that the introduction of h leads to the hybridization of two degenerate spin modes due to the appearance of a nondiagonal on a, b spin-spin Green's functions. The comparison of the theory with the exact diagonalization study and with results on inelastic neutron scattering experiments is discussed at T = 0. We discuss also the correspondence of the theory to the existing theories, which allow only two spin excitations modes for the total S(k,w).
