In solid state materials, numerous electrons are interacting due to Coulomb interactions. The standard Fermi liquid theory describes interacting electron systems approximately as a collection of non-interacting quasiparticles. However, materials beyond Fermi liquid theory do exist and can give rise to intriguing quantum phenomena such as “fractionalized” excitations in strongly-correlated materials. Their investigation is critical to fundamental physics and future quantum technologies but is challenging in material realizations and experimental detections. Recent progress of 2D materials, especially their moiré engineering, has made it a promising platform for studying novel quantum phases. In this talk, I will present my PhD research about strongly correlated states in monolayer tungsten ditelluride (WTe2) and its moiré structures. In twisted bilayer WTe2 (tWTe2), a new 2D anisotropic state was observed, mimicking an array of 1D Luttinger Liquids (LLs). Unlike Fermi liquids, electrons in LLs are strongly correlated and fractionalize into spin and charge modes separately. Our study expands the conventionally 1D LL physics to 2D, offering a platform for studying non-Fermi liquids in uncharted regime. I will also introduce novel probing techniques of monolayer WTe2 superconducting and insulating states including the coupling to a superconducting resonator circuit and THz optics.

Adviser: Sanfeng Wu