Emergence of a reentrant insulating phase around v=1/3 in a series of GaAs/AlGaAs quantum wells with varying well widths

We report on magneto-transport measurements of a systematic set of five GaAs/AlGaAs quantum wells with well widths ranging from 7.9 to 33.0 nm. We find that as L is decreased into the regime where the zero-field mobility is limited due to surface roughness, a reentrant insulating phase around filling fraction v = 1/3 emerges. As L is decreased further, only a single insulating phase is observed for v 1. (C) 2007 Elsevier B.V. All rights reserved.