Heat capacity of Gd0.06Er0.94Al2 in magnetic fields

We have measured the specific heat of an arc-melted specimen of Gd0.06Er0.94Al2 in applied magnetic fields of 1, 3, 5, and 8 T from 4.5 to 40 K, and in zero field from 1.4 to 98 K. Inspection of entropy versus temperature with the lattice included shows that the maximum adiabatic cooling is 13 K and occurs from 30 K at 8 T to 17 K at zero field. With our previous magnetization measurements on Gd0.5Er0.5Al2, our data indicate that substitution of Gd for Er in this crystalline environment does not significantly increase the magnetocrystalline anisotropy. The solid solution is magnetically soft and most of the magnetic entropy changes occur below 30 K.