[Colloquium] Electron Solids in Atomically Thin Semiconductors

Feng Wang, UC Berkeley

Title: Electron Solids in Atomically Thin Semiconductors

Abstract: Free electrons in a semiconductor are usually described by weakly interacting Fermi liquid that conducts electricity. However, Wigner pointed out 90 years ago that Coulomb interactions become dominant at low electron density and low temperature, resulting in the formation of the electron solid, known as the Wigner crystals. Atomically thin two-dimensional (2D) semiconductors and heterostructures offer a highly tunable platform for exploring the electron solid phases. In this talk, I will describe our effort to directly image the Wigner crystal and its quantum melting behavior in atomically thin semiconductors using scanning tunneling microscopy. I will also discuss rich variety of Wigner solid behaviors that can emerge when one-dimensional and two-dimensional potentials are imposed onto the atomically thin semiconductors.