Determination of the longitudinal thermo-galvanomagnetic coefficients

The problems associated with the non-ideal boundary conditions that usually hold in practical galvanomagnetic and thermomagnetic measurements are described. It is then proposed that a novel technique should be used to overcome these problems. This technique involves the use of samples of different length-to-width ratio. Any particular longitudinal thermo-galvanomagnetic coefficient varies with this ratio and it is shown how the value of the coefficient for zero transverse flow can be obtained. All the potential measurements are made at the end contacts and there is no need to apply probes to the side faces. This method is especially easy to use for polycrystalline material since a single sample, in which the width and breadth are different, is then sufficient. Examples of the applications of the technique to a Bi-Sb alloy are given