Two-dimensional holes at high magnetic fields

The magnetotransport properties of two-dimensional holes in GaAsGaAlAs heterostructures are reviewed, with emphasis in the high field regime. Temperature dependence measurements of the 1 3 and 2 3 states of the fractional quantum Hall effect yield activation energies comparable to those of 2D electrons, but that are not directly correlated with low-temperature mobilities. © 1986.