Variational bound for the energy of two-dimensional quantum antiferromagnet
Abstract
Description
We obtain the variational upper bound for the ground- state energy of two-dimensional antiferromagnetic Heisenberg model on a square lattice at arbitrary value of the anisotropy parameter using the two-dimensional generalization of Jordan-Wigner transformation. Our result can be considered as an upper bound for the perturbation theory series about the Ising limit.
7 pages, LaTex, JETP Letters (Pisma v ZhETF) 57 (1993) 796-800
7 pages, LaTex, JETP Letters (Pisma v ZhETF) 57 (1993) 796-800