Heat Capacity of the Two-Dimensional Electron Gas in GaAs/AlGaAs Multiple Quantum Well Structures

We apply the technique of ac calorimetry to a study of the heat capacity of the two-dimensional electron gas (2DEG) in GaAs/AlGaAs multiple quantum well structures, and our results differ from those previously reported by Gornik et al. In sweeps of magnetic field B below 2.3K, the 2DEG contribution to the sample heat capacity is identifiable as oscillations of relative size 0.1-0.2% periodic in 1/B. The oscillations appear as pointed peaks, when B is such that the Fermi energy lies within one Landau level, separated by smooth valleys.