Electron-electron interactions and the paired-to-nematic quantum phase transition in the second Landau level
K. A. Schreiber (Purdue University)
N. Samkharadze (TU Delft - QCD/Vandersypen Lab, Purdue University)
G. C. Gardner (Purdue University)
Y. Lyanda-Geller (Purdue University)
Michael J. Manfra (Purdue University)
L. N. Pfeiffer (Princeton University)
K. W. West (Princeton University)
G. A. Csáthy (Purdue University)
More Info
expand_more
Other than for strictly personal use, it is not permitted to download, forward or distribute the text or part of it, without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license such as Creative Commons.
Abstract
In spite of its ubiquity in strongly correlated systems, the competition of paired and nematic ground states remains poorly understood. Recently such a competition was reported in the two-dimensional electron gas at filling factor ν = 5/2. At this filling factor a pressure-induced quantum phase transition was observed from the paired fractional quantum Hall state to the quantum Hall nematic. Here we show that the pressure-induced paired-to-nematic transition also develops at ν = 7/2, demonstrating therefore this transition in both spin branches of the second orbital Landau level. However, we find that pressure is not the only parameter controlling this transition. Indeed, ground states consistent with those observed under pressure also develop in a sample measured at ambient pressure, but in which the electron-electron interaction was tuned close to its value at the quantum critical point. Our experiments suggest that electron-electron interactions play a critical role in driving the paired-to-nematic transition.