Effective nuclear temperature in a fluctuating spin system
E. Bertin, J. A. Hodges, J. -P. Bouchaud, P. Bonville, J. P. Sanchez, P. Vuillet
Abstract
We report on very low temperature (27 mK) Mossbauer absorption spectra on Gd 155 in the Heisenberg frustrated antiferromagnets Gd2 Sn2 O7 (GdSn) and Gd2 Ti2 O7. We show that electronic fluctuations of correlated Gd3+ moments are present near T=0 in GdSn by observing that the hyperfine levels are out of equilibrium. Using a model spin 1/2 system, submitted to a magnetic (hyperfine) field reversing randomly in time, we find an analytical expression for the stationary probability distribution of the level populations (or magnetization). This quantity is a simple function of the ratio of the nuclear relaxation time to the average electronic flip time. These two time scales are found to be of the same magnitude in GdSn, and we discuss a relevant mechanism for nuclear relaxation and the influence of electronic fluctuations on the nuclear specific heat.
Create a lesson
Related papers
Knots in Condensed Matters
Y. M. Cho
Bouchaud's model exhibits two different aging regimes in dimension one
Gerard Ben Arous, Jiri Cerny
Periodic diffraction patterns for 1D quasicrystals
Pawel Buczek, Lorenzo Sadun, Janusz Wolny
Adiabatic association of ultracold molecules via magnetic field tunable interactions
Krzysztof Goral, Thorsten Koehler, Simon A. Gardiner et al.
High-Temperature Atomic Superfluidity in Lattice Boson-Fermion Mixtures
F. Illuminati, A. Albus
Constructive Methods of Invariant Manifolds for Kinetic Problems
A. N. Gorban, I. V. Karlin, A. Yu. Zinovyev