Grüneisen parameters of germanium-silicon alloy

Using a technique described recently by Gauster, a direct determination of the Grüneisen parameter was carried out for GeSi (80 at.% Si) alloy between 130 and 300 K. The value varied smoothly between 0.57 at 300 K and 0.22 at 130 K. The measured Grüneisen parameter agreed within the experimental error with the values predicted by an elastic continuum model which used the Ge and Si properties as inputs.