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【Abstract】

In this talk, we introduce density-imbalanced electron-hole bilayers at a commensurate 2:1 density ratio as a platform for realizing novel phases of electrons, excitons, and trions. Through the independently tunable carrier densities and interlayer spacing, competition between kinetic energy, intralayer repulsion, and interlayer attraction yields a rich phase diagram of strong-coupling phases. By a combination of theoretical analysis and numerical calculation, we find a variety of phases in different parameter regions, including quantum crystals of electrons, excitons, and trions. We also propose an “excitonic supersolid” phase featuring an exciton superfluid permeating through an electron Wigner crystal. The material realization and experimental signatures of our phases are discussed in the context of recent experiments on semiconductor transition metal dichalcogenide bilayers. We also discuss recent computational work applying variational neural network wavefunctions to mapping out the phase diagram of strongly correlated systems such as the electron-hole bilayer.