Quantum transport in n-type and p-type modulation-doped mercury telluride quantum wells

• Published in: Physica. E, Low-dimensional systems & nanostructures Vol. 6; no. 1; pp. 713 - 717
• Main Authors: Landwehr, G., Gerschütz, J., Oehling, S., Pfeuffer-Jeschke, A., Latussek, V., Becker, C.R.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.02.2000
• Subjects: Band structure; HgTe; Magnetotransport; Quantum wells; Band structure; 71.20.M; HgTe; Quantum wells; 72.20.M; 73.61.G; Magnetotransport
• ISSN: 1386-9477; 1873-1759
• DOI: 10.1016/S1386-9477(99)00179-4

Asymmetrically modulation-doped HgTe quantum wells of (0 0 1) orientation were produced by molecular beam epitaxy. N-type doping was achieved with iodine and p-type doping by the incorporation of nitrogen. At 4.2 K the n-type samples have electron mobilities up to 10 5 cm 2/ Vs , the maximum Hall mobility of the p-type specimens is around 2×10 4 cm 2/ Vs . Very pronounced Shubnikov–de Haas oscillations were observed in both n-type and p-type samples. In the n-type specimens the quantum oscillations persisted up to temperatures of 60 K. The Shubnikov–de Haas oscillations in the p-type samples were highly irregular. Because the data cannot be explained without detailed theoretical calculations of Landau levels for the heterostructure self consistent Hartree calculations were performed using a 8×8 k· p model. The magnetic field-dependent density of states was calculated. More regular oscillations are predicted at higher magnetic fields approaching 30 T.