Apparatus for thermopower measurements on organic conductors

Abstract

An apparatus is described for making transport measurements, especially thermopower, on single crystals of highly conducting organic solids. It is designed specifically for small fragile anisotropic samples such as TCNQ salts. The temperature range is 400−1.2 k. A slow ac technique is used so that stray thermal emfs are eliminated and measurements can be taken with a small (0.5 K) temperature gradient for good temperature resolution in regions where the transport properties are changing quickly.