Year: 2020
Type: article
Abstract: A sufficiently large perpendicular magnetic field quenches the kinetic (Fermi) energy of an interacting two-dimensional (2D) system of fermions, making them susceptible to the formation of a Wigner solid (WS) phase in which the charged carriers organize themselves in a periodic array in order to minimize their Coulomb repulsion energy. In low-disorder 2D electron systems confined to modulation-doped GaAs heterostructures, signatures of a magnetic-field-induced WS appear at low temperatures and very small Landau level filling factors (ν≃1/5). In dilute GaAs 2D hole systems, on the other hand, thanks to the larger hole effective mass and the ensuing Landau level mixing, the WS forms at relatively higher fillings (ν≃1/3). Here we report our measurements of the fundamental temperature vs filling phase diagram for the 2D holes' WS-liquid thermal melting. Moreover, via changing the 2D hole density, we also probe their Landau level mixing vs filling WS-liquid quantum melting phase diagram. We find our data to be in good agreement with the results of very recent calculations, although intriguing subtleties remain.
Source: Physical Review Letters
Authors: Meng K. Ma, K. A. Villegas Rosales, H. Deng, Y. J. Chung, L. N. Pfeiffer, K. W. West, K. W. Baldwin, R. Winkler, M. Shayegan
Institutions: Princeton University, Northern Illinois University
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Awards: Princeton Center for Complex Materials, Supplying the Quantum Materials Community with Record-Mobility Gallium Arsenide Quantum Wells, Probing Exotic Phases of Two-dimensional Electrons in Unconventional Systems, Quantum Materials Workshops and Scientist Exchange Program, Electronic spin and valley degrees of freedom - based novel quantum devices, MAGNETO-TRANSPORT IN GAAS TWO-DIMENSIONAL HOLE SYSTEMS
OpenAlex ID: W3035496227