Magnetoconductance Oscillations In InGaAs/GaAs Lateral Surface Superlattices

Lateral surface superlattice (LSSL) structures have been prepared on MBE grown In0.2Ga0.8As/GaAs strained layers by electron beam lithography and metal lift-off processing. The LSSL is induced by a 160-nm period Ti/Pt/Au grid replacing the normal metal gate of a HEMT. Magnetoconductance measurements made at 5K show universal conductance fluctuations with an amplitude of 0.1e2/h and Aharonov-Bohm type periodic oscillations with h/e periodicity in the flux coupled through each cell of the superlattice. To the best of our knowledge, this is the first observation of Aharonov-Bohm effect in a solid state system that was not in a ring structure.