Abstract
In the inverted-band regime of HgTe/CdTe quantum wells, the lowest Landau level of the lowest conduction subband and the highest Landau level of the topmost valence subband are predicted to cross at a critical magnetic field We study this crossing experimentally with far-infrared Fourier-transform spectroscopy in a gated HgTe/CdTe quantum well with tunable electron density. The crossing point is identified by a characteristic exchange of oscillator strength between the two transitions involved, one being a cyclotron resonance, the other an intersubband resonance. The experimental resonance positions, the oscillator strengths as well as the value of are in good agreement with theoretical results of a 6×6 k⋅p model evaluated for the growth direction.
- Received 11 December 1997
DOI:https://doi.org/10.1103/PhysRevB.57.14772
©1998 American Physical Society