Measurement of spin correlation lengths in Eu sub (.54) Sr sib (.46) S by elastic light scattering.

Elastic light scattering has been used to measure the spin correlation length xi, in the reentrant spin glass Eu sub (.54) Sr sub (.46) S. Xi is found to change only modestly in going from the ferromagnetic to the spin glass (SG) phase, i.e., from 2700angstroms to 2000angstroms. This result may be reconciled with neutron experiments which find xi ~ 100angstroms in the SG regime by ascribing the light scattering in the SG regime to the remnant magnetization of the original ferromagnetic regions.