Relaxation Method for Specific Heat Measurement

Thermal relaxation calorimetery is an important method for performing specific heat measurements of small samples at low temperatures. Crystals with a mass of 1 mg can be measured precisely down to a temperature of 50mK. The sample relaxation time τ~C/κ is measured while maintaining both the bath temperature and external parameters constant.

The sample is placed on a platform which contains a heater and a thermometer. The platform is connected by a thermal link to a reservoir at a constant temperature. To perform the measurement, a well defined constant heat pulse is applied to raise the temperature of the platform. The heater power is then turned off and the temperature decays to temperature of the reservoir and the heat capacity is obtained from the rate at which the decay occurs