Low-Temperature Properties
of Electronic System Using
a Schick-Type Microchip Calorimeter
– Discussion on the Appropriate Condition
for Ac Method

Highly sensitive calorimetric measurements at low temperature for small-sized samples are required in the field of condensed matter physics. To get enough resolution at low temperatures, heat capacity of addenda should be reduced. Commercially available microchip TCG-3880 (Xensor-Integration Corp.) is introduced by Minakov and Schick et al., as high-speed calorimetry technique. Using this microchip, we built a heat capacity measurement system by ac method. In ac method, selection of the appropriate frequency is very important for heat capacity measurements. Therefore, we examined frequency dependences of temperature amplitude. These results imply that this system should be utilized at low frequency region and 4 Hz in the case of vacuum condition.

(by Y. Inoue & Y. Nakazawa)

	Photo 1. (a) Microchip TCG-3880. (b) A measurement probe designed for ac calorimetry using TCG-3880. (c) A cryostat system with 15 T superconducting magnet.		Fig. 1. Block diagram of the detection system of the present calorimeter.
			Fig. 2. Frequency dependence of temperature amplitudes obtained at 13, 60, 115, 160, 200, and 240 K.