Evidence of Zero-Field Wigner Solids in Ultrathin Films of Cadmium Arsenide
Year: 2024
Type: article
Abstract: The quantum Wigner crystal is a many-body state where Coulombic repulsion quenches the kinetic energy of electrons, causing them to crystallize into a lattice. Experimental realization of a quantum Wigner crystal at zero magnetic field has been a long-sought goal. Here, we report on the experimental evidence of a Wigner solid in ultra-thin films of cadmium arsenide ( Cd 3 As 2 ) at zero magnetic field. We show that a finite bias depins the domains and produces an unusually sharp-threshold current-voltage behavior. Hysteresis and voltage fluctuations point to domain motion across the pinning potential and disappear at finite temperature as thermal fluctuations overcome the potential. The application of a small magnetic field destroys the Wigner solid, pointing to an unconventional origin. We use Landau-level spectroscopy to show that the formation of the Wigner solid is closely connected to a topological transition as the film thickness is reduced. Published by the American Physical Society 2024
Source: Physical Review X
Institution: University of California, Santa Barbara
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $4,200
OpenAlex ID: W4404137585