Shubnikov-de Haas Effect in InGaSb/InAs superlattices.

Magneto-transport measurements have been made on strain-free In0.25Ga0.75Sb/InAs superlattices grown on GaSb substrates. The superior structural quality of these superlattices compared to older materials in the literature resulted in a much higher resolution of the Shubnikov-de Haas oscillations. Three separate conduction channels were observed. Measurements with the magnetic field in the plane of the sample indicated that the channel with the longer period was due to three dimensional-like conduction within the superlattice while the other two channels showed two dimensional behavior most likely associated with conduction at the surface or interfaces between the superlattice and bulk-like layers. Comparison with multi-carrier analysis indicated that the channel with intermediate period was due to hole conduction while the others were due to electron conduction. Oscillations were observed at temperatures up to 20?K. The concentration of the superlattice channel at low temperature was 5.93?×?1015 cm-3 while those of the two dimensional hole and electron channels were 1.64?×?1011 cm-2 and 5.20?×?1011 cm-2. [ABSTRACT FROM AUTHOR]