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

ALBERTO CAMJAYI; MARCELO JAVIER ROZENBERG

PHYSICAL REVIEW LETTERS

Año: 2003 vol. 90 p. 2172021 - 2172024

0031-9007

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 observe 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 remarkable qualitative agreement with various experiments on the quantum frustrated magnet SrCr_{9p}Ga_{12-9p}O_{19}.