Spin-glass like states in the ferrimagnet FeCr2S4

Magnetisation measurements on FeCr2S4 single crystals revealed a re-entrant behaviour at temperatures below 60 K. Sharp spin-glass like changes of zer o-field-cooled and thermoremanent magnetisations, coercive force and strong time-dependent magnetisation relaxation below 20 K were also found. The ob served effects are considered to be a result of fluctuating competing excha nge interactions along with the high magnetocrystalline anisotropy of tetra hedral Fe ions strongly antiferromagnetically coupled with Cr ions. (C) 200 1 Elsevier Science B.V, All rights reserved.