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V. Cannella and J. A. Mydosh measured low-field magnetic susceptibility of gold-iron alloys using a mutual inductance bridge. Moving samples into and out of the pickup arrangement separated their signal from the background. Cooling revealed sharp susceptibility cusps; changing concentration, sample shape and applied magnetic field tested their interpretation. Larger fields rounded the peaks. Their 1972 paper interpreted low-concentration ordering in antiferromagnetic terms: the cusp alone did not demonstrate Parisi's later theory.^[ref]

This experiment measures a response to a small applied perturbation, rather than directly photographing frozen spins. Comparing field strengths is essential because the probing magnetic field itself changes the response.^[ref]

An experimental physicist who, with John A. Mydosh, studied magnetic ordering in gold-iron alloys. Measurements of thermoelectric power and low-field magnetic susceptibility across iron concentrations linked transport anomalies with changes in magnetic behavior. Sharp susceptibility features provided a way to track ordering in a chemically disordered material, motivating the study of competing interactions in spin glasses.^[ref]