Wigner crystallization and metal-insulator transition of two-dimensional holes in GaAs/AlGaAs at B=0

Jongsoo Yoon; C. C. Li; D. Shahar; D. C. Tsui; M. Shayegan

doi:10.1103/PhysRevLett.82.1744

paper

Wigner crystallization and metal-insulator transition of two-dimensional holes in GaAs/AlGaAs at B=0

arXiv:cond-mat/9807235 · doi:10.1103/PhysRevLett.82.1744

Abstract

We report the transport properties of a low disorder two-dimensional hole system (2DHS) in the GaAs/AlGaAs heterostructure, which has an unprecedentedly high peak mobility of $7 \times 1 0^{5} c m^{2} / V s$ , with hole density of $4.8 \times 1 0^{9} c m^{- 2} < p < 3.72 \times 1 0^{10} c m^{- 2}$ in the temperature range of $50 m K < T < 1.3 K$ . From their T, p, and electric field dependences, we find that the metal-insulator transition in zero magnetic field in this exceptionally clean 2DHS occurs at $r_{s} = 35.1 \pm 0.9$ , which is in good agreement with the critical $r_{s}$ for Wigner crystallization $r_{s}^{c} = 37 \pm 5$ , predicted by Tanatar and Ceperley for an ideally clean 2D system.

4 pages, 4 Postscript figures