Biomedical subjects
Publications and source records attributed to Dorothée Petit.
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For five different Heisenberg spin glass systems, torque experiments were performed in applied magnetic fields up to 4 T. The Dzyaloshinski-Moriya random anisotropy strengths, the in-field torque onset temperatures, and the torque relaxation were measured. Critical exponents were estimated independently using a standard protocol. The data are strong evidence for a true spin glass ordered state which survives under high applied magnetic fields; they can be interpreted consistently in terms of a chiral ordering model with replica symmetry breaking as proposed by Kawamura and co-workers.