Influence of a magnetic field on the magnetoelasticity of commensurate spin-density-wave Cr-Ru and Cr-Si alloy single crystals

Previously reported attempts to produce a single-Q commensurate (C) spin-de nsity-wave (SDW) state in a dilute Cr alloy by magnetic held cooling throug h the Neel temperature (T-N), were unsuccessful. In the present study the i nfluence of a cooling field of 4.5 T on the magnetoelasticity of Cr + 0.3 a t.% Ru and Cr + 1.6 at.% Si alloy single crystals, both having CSDW phases below T-N, are reported. The results show that cooling the Cr + 0.3 at.% Ru crystal through T-N in a field of 4.5 T has no influence on the first-orde r commensurate-incommensurate SDW magnetic phase transition. On the other h and, cooling the Cr + 1.6 at.% Si crystal in a field of 4.5 T through T-N n oticeably affects the elasticity in the CSDW state, suggesting a condensati on of part of this crystal into a single-Q CSDW phase. (C) 1999 Elsevier Sc ience S.A. All rights reserved.