Low-temperature specific heat of LaAl2:Gd in magnetic fields up to 4900 Oe

The specific heat of La${\mathrm{Al}}_2$:Gd was measured between 1.3 and 6 K for Gd concentrations of 0, 2.0, 3.0, and 6.0 at.% in various applied magnetic fields up to 4900 Oe. Broad peaks associated with spin glass transitions in zero field were shifted to higher temperatures by the applied field. The field dependence of the magnetic specific heat follows a law of corresponding states and exhibits several characteristics predicted by molecular-field theories based on the Ruderman-Kittel-Kasuya-Yosida interaction. For no value of applied field were the results consistent with the absence of magnetic order as suggested by nuclear relaxation measurements.