Reorientation of the anisotropic phase of a 2D electron system using a very small density modulation

ORAL

Abstract

A high-quality two-dimensional electron system (2DES) confined to a GaAs quantum well typically exhibits isotropic transport coefficients when the Fermi level resides in the first excited ($N=1$) Landau level. Adding an in-plane magnetic field ($B_{||}$) leads to an anisotropic (stripe) phase with the stripes oriented perpendicular to the $B_{||}$ direction. We study how a periodic density modulation of the 2DES, induced by a surface strain grating from lines of negative electron-beam resist, affects the orientation of the $\nu=7/2$ stripe phase. Our results reveal that the external potential modulation competes against the $B_{||}$-induced orientational order of the stripe phase. Even a minute ($\sim0.5\%$) density modulation is sufficient to reorient the stripes at $\nu=7/2$ along the direction of the surface grating.

Authors

  • Md Shafayat Hossain

    • Princeton University
  • M A MUEED

    • Princeton University
  • Hao Deng

    • Princeton University
    • Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544
  • Mansour Shayegan

    • Princeton University
    • Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544
  • Loren Pfeiffer

    • Princeton University
    • Dept. of Electrical Engineering, Princeton University, Princeton, NJ
    • Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544
    • Department of Electrical Engineering, Princeton University
    • Princeton
  • Ken West

    • Princeton University
    • Dept. of Electrical Engineering, Princeton University, Princeton, NJ
    • Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544
    • Princeton
  • Kirk Baldwin

    • Princeton University