Specific Heat of Dilute Alloys of Tin in Indium between 0.5 and 1.7 K

Specific-heat measurements were made on dilute alloys of tin in indium in the temperature range 0.5 to 1.7 K. For tin concentrations of 0,0.8,2.1,4.9, and 9.7 at.%, $\gamma$ (electronic specific heat) values of 1.66, 1.66, 1.74, 1.88, and 1.92 mJ/mole ${\mathrm{K}}^2$ were found. This represents a more rapid increase in $\gamma$ than would be predicted on the assumption of rigid parabolic bands, and may be due to filling of third-zone $\alpha$ arms. The variation of $\gamma$ with concentration is different from that of the Knight shift.