Abstract:
The magnetoabsorption in magnetic fields as high as 40 T is investigated at $T >$ 77 K in HgTe/CdHgTe quantum-well heterostructures ($d_{\mathrm{QW}}\approx$ 8 nm). The spectra reveal two lines associated both with intraband transition from the lower Landau level in the conduction band and with interband transition. It is shown that the band structure in these systems changes from inverted to normal with increasing temperature.