Dynamic spin susceptibility in the t-J model
Abstract
A relaxation-function theory for the dynamic spin susceptibility in the -- model is presented. By a sum-rule-conserving generalized mean-field approximation (GMFA), the two-spin correlation functions of arbitrary range, the staggered magnetization, the uniform static susceptibility, and the antiferromagnetic correlation length are calculated in a wide region of hole doping and temperaturs. A good agreement with available exact diagonalization (ED) data is found. The correlation length is in reasonable agreement with neutron-scattering experiments on La_{2-\delta}Sr_\delta)CuO_4. Going beyond the GMFA, the self-energy is calculated in the mode-coupling approximation. The spin dynamics at arbitrary frequencies and wave vectors is studied for various temperatures and hole doping. At low doping a spin-wave-type behavior is found as in the Heisenberg model, while at higher doping a strong damping caused by hole hopping occurs, and a relaxation-type spin dynamics is observed in agreement with the ED results. The local spin susceptibility and its (\omega/T) scaling behavior are calculated in a reasonable agreement with experimental and ED data.
Cite
@article{arxiv.0908.2557,
title = {Dynamic spin susceptibility in the t-J model},
author = {A. A. Vladimirov and D. Ihle and N. M. Plakida},
journal= {arXiv preprint arXiv:0908.2557},
year = {2015}
}
Comments
13 pages, 14 figures