We report measurements of the specific heat of ${\mathrm{La}}_{0.67}$${\mathrm{Ba}}_{0.33}$Mn${\mathrm{O}}_3$ and ${\mathrm{La}}_{0.8}$${\mathrm{Ca}}_{0.2}$Mn${\mathrm{O}}_3$ for temperatures $2<T<\mathrm{}15\mathrm{}$ K. These materials are ferromagnetic metallic oxides which exhibit colossal magnetoresistance. We find that above 3 K the specific heat has terms proportional to $T$ and $T^3$, but a $T^{\frac{3}{2}}$ term, as might be expected from the excitation of ferromagnetic spin waves, cannot be resolved outside of the precision of the data. The cubic term gives Debye temperatures of 400±17 K, and the linear term gives electron densities of states which are enhanced over band-structure estimates.

• Received 14 June 1996

DOI:https://doi.org/10.1103/PhysRevB.54.14926