Freezing of magnetic domain motion in a reentrant spin glass as seen by elastic measurements

Abstract

We report here measurements of elastic modulus of a reentrant spin glass (RSG) across the reentrant transition temperature (T_sg). By measuring the Young modulus (E) in a magnetic field we obtained the "ΔE" effect, which is the contribution of the ferromagnetic domains to the E. While a small but finite "ΔE" effect has been observed in the RSG below the first ferromagnetic transition temperature (T_c), it vanishes for T<T_sb. In contrast to the RSG, in a ferromagnet the "ΔE" effect is temperature independent at T«T_c. We explained this observation as arising due to freezing of magnetic domain motion at or below T_sg. This experiment in conjunction with previous magnetic experiments show that the observed "reentrant" transition is determined by freezing of domain motion.