The Low Temperature Specific Heat of an Aluminium-Manganese Alloy

This is the authors' abstract. We don't add key points for this paper.

Aluminium-manganese alloys do not show the resistance-minimum phenomena often found in dilute alloys containing transition metals, but anomalous thermoelectric powers are observed. Alloy systems which do show the resistance minimum also have large specific heat anomalies at low temperatures. It was therefore of interest to see whether specific heat anomalies occurred in the aluminium-manganese system. Measurements of the specific heat of pure aluminium and of an alloy containing 0.045 atomic% manganese were therefore made in the temperature range 0.4° to 1.5°K. In the normal state the specific heats of the two samples are the same. Thus a specific heat anomaly of the type found in systems showing the resistance minimum does not occur. The superconducting transition temperature of the alloy is about 0.84°K (compared with 1.174±0.002°K for pure aluminium) but the transition remains sharp (width less than 0.001 deg K) and of the second order. The reduced electronic specific heats in the superconducting state C es /γ T c , when given in terms of reduced temperature T c / T , are identical.