Finite-temperature correlations in a quantum spin chain near saturation
Abstract
Inelastic neutron-scattering and finite-temperature density matrix renormalization group (DMRG) calculations are used to investigate the spin excitation spectrum of the Heisenberg spin chain compound KCuSOCl at several temperatures in a magnetic field near saturation. Critical correlations characteristic of the predicted , quantum phase transition occurring at saturation are shown to be consistent with the observed neutron spectra. The data is well described with a scaling function computed using a free fermion description of the spins, valid close to saturation, and the corresponding scaling limits. One of the most prominent non-universal spectral features of the data is a novel thermally activated longitudinal mode that remains underdamped across most of the Brillouin zone.
Keywords
Cite
@article{arxiv.1707.05243,
title = {Finite-temperature correlations in a quantum spin chain near saturation},
author = {Dominic Blosser and Noam Kestin and Kirill Yu. Povarov and Robert Bewley and Emanuele Coira and Thierry Giamarchi and Andrey Zheludev},
journal= {arXiv preprint arXiv:1707.05243},
year = {2017}
}