Quantum and thermal fluctuations in the SU(N) Heisenberg spin-glass model near the quantum critical point

TL;DR

This paper investigates quantum and thermal fluctuations in the SU(N) Heisenberg spin-glass model near the quantum critical point, revealing spectral weight transfers and unusual low-temperature specific heat behavior, with implications for frustrated magnetic materials.

Contribution

It provides a large-N analytical solution for the SU(N) Heisenberg spin-glass model focusing on fluctuation effects near the quantum critical point.

Findings

Spectral weight transfer due to quantum and thermal fluctuations.

Unusual T^2 dependence of specific heat at low temperatures.

Qualitative agreement with experiments on frustrated magnet SrCr_{9p}Ga_{12-9p}O_{19}.

Abstract

We solve for the SU(N) Heisenberg spin-glass in the limit of large N focusing on small S and T. We study the effect of quantum and thermal fluctuations in the frequency dependent response function and observed interesting transfers of spectral weight. We compute the T-dependence of the order parameter and the specific heat and find an unusual T^2 behavior for the latter at low temperatures in the spin-glass phase. We find a remarkable qualitative agreement with various experiments on the quantum frustrated magnet SrCr_{9p}Ga_{12-9p}O_{19}.