Magnetocapacitance measurements in GaAs heterostructures

Measurements of the magnetocapacitance of a two-dimensional electron gas in high mobility GaAs(Ga, Al)As heterostructure confirm, for the first time, the relationship between the density of states and the capacitance of a two-dimensional electron gas. We present the first magnetocapacitance measurements in the fractionally quantized Hall regime. © 1986.