Fabrication and characterization of nanopatterned LaAlO3/SrTiO3 heterostructures

Abstract

We report the fabrication of nanopatterned conduction channels and electrical transport of a two-dimensional electron gas formed at a LaAlO3/SrTiO3 heterointerface. The nanoscale channels are formed by electron beam lithography and Ar-ion etching. The negative magnetoconductance data observed at low temperature are attributed to the weak antilocalization effect due to the strong spin-orbit interaction inherent in the electron gas at the heterointerface whereas the conductance fluctuations are caused by quantum interference between the electron wavefunctions. The gatedependent characteristic parameters, obtained using the Maekawa-Fukuyama model, reveal that the spin-orbit interaction in the nanopatterned metal-oxide heterostructure is gate-tunable, which will be useful for building spintronic devices.