MAGNETOTRANSPORT OF ELECTRONS IN ARRAYS OF WIRES IN SI SI0.7GE0.3 HETEROSTRUCTURES/

Magnetotransport parallel to quantum wires in Si/SiGe heterostructures was conducted in the quasi-ballistic regime. We observed magnetoresis tance oscillations due to the depopulation of quasi-one dimensional su b-bands, and at low magnetic fields a well pronounced peak arising fro m diffuse scattering at the wire boundaries emerges. The analysis of t hese features yields a maximum sub-band spacing of 1 meV at a correspo nding wire width of 70 nm. Electron transport perpendicular to shallow etched wires was investigated in lateral superlattices with a period of 350 nm. At magnetic fields below 0.7 T magnetotransport measurement s show commensurability oscillations corresponding up to three periods of the wire grating. However, the modulated lateral potential is not purely sinusoidal, resulting in a splitting of the commensurability os cillations.