Interplay between sheet resistance increase and magnetotransport properties in {rm LaAlO₃}/{rm SrTiO₃}

We find that the sheet resistance ($R_s$) of patterned samples of ${\rm LaAlO_3}/{\rm SrTiO_3}$ with a length scale of several microns may increase significantly at low temperatures in connection with driving electrical currents and applying in-plane magnetic fields. As the samples are warmed up, $R_s$ recovers to its original value with accelerated recovery near ${\rm 70 \ K}$ and ${\rm 160 \ K}$. Concomitantly with the increase in $R_s$, the carrier density and the mobility decrease and magnetotransport properties which may be linked to magnetism are suppressed.