Communications in Theoretical Physics ›› 1993, Vol. 19 ›› Issue (2): 129-138.

• General •     Next Articles

The Staggered Magnetization of the Square Lattice Frustrated Heisenberg Model

Shi-Min CUI   

  1. Institute of Condensed Matter Physics and Department of Physics Shanghai Jiao Tong University, Shanghai 200030, China
  • Received: 1992-03-05 Published: 1993-03-15
  • Funding Information: 

    The project partially supported by National Natural Science Foundation of China through Grant No.19004007.

Abstract: Spin-wave expansion is used to evaluate the staggered magnetization of frustrated antiferromagnetic (AF) Heisenberg model with next-nearest-neighbor exchange couplings on a square lattice to the order O(1/S) at zero temperature. It is shown that the O(1/S) order correction increases the staggered magnetization and its presence invalidates the conventional spin- wave conclusions at large frustrations. We apply the mean-field approximation to deal with the quartic terms in the Hamiltonian of the Holstein-Primakoff transformation. A phaqe diagtam is obtained, suggesting that the NCel order is not destroyed for S≥1 at any frustration, while for S = 1/2 there may exist a disordered phase for strong frustrations.