Cyclotron resonance at microwave frequencies in two-dimensional hole system in AlGaAs/GaAs quantum wells

Cyclotron resonance at the microwave frequency is used to measure the band edge mass (m(b)) in the two-dimensional hole (2DH) system, confined in 30 nm quantum wells in the Al0.1Ga0.9As/GaAs/Al0.1Ga0.9As heterostructures. We find that for 2DH density pless than or equal to1.0x10(10) cm(-2), m(b) is nearly constant, similar to0.35m(e). It increases with increasing density, to similar to0.5m(e) at p=7.4x10(10) cm(-2). (C) 2003 American Institute of Physics.