Observation of an electronic microemulsion phase emerging from a quantum crystal-to-liquid transition

Abstract

Strongly interacting electronic systems possess rich phase diagrams resulting from the competition between different quantum ground states. A general mechanism that relieves this frustration is the emergence of microemulsion phases, where regions of different phase self-organize across multiple length scales. The experimental characterization of these phases often poses significant challenges, as the long-range Coulomb interaction microscopically mingles the competing states. Here, we use cryogenic reflectance and magneto-optical spectroscopy to observe the signatures of the mixed state between an electronic Wigner crystal and an electron liquid in a MoSe2 monolayer. We find that the transit into this 'microemulsion' state is marked by anomalies in exciton reflectance, spin susceptibility, and Umklapp scattering, establishing it as a distinct phase of electronic matter. Our study of the two-dimensional electronic microemulsion phase elucidates the physics of novel correlated electron states with strong Coulomb interactions.

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Cited by in corpus (12)

• Optical signatures of interlayer electron coherence in a bilayer semiconductor
• Critical gate distance for Wigner crystallization in the two-dimensional electron gas
• Magnetism of the Bilayer Wigner Crystal
• Wideband covariance magnetometry below the diffraction limit
• Impact of an electron Wigner crystal on exciton propagation
• Defect liquids in a weakly imbalanced bilayer Wigner Crystal
• Exchange Interactions of a Wigner Crystal in a Magnetic Field and Berry Curvature: Multi-Particle Tunneling through Complex Trajectories
• Spin-triplet paired Wigner crystal stabilized by quantum geometry
• Elementary Excitations, Melting Temperature, and Correlation Energy in Wigner Crystals
• Quantum melting a Wigner crystal into Hall liquids
• Exciton interacting with the phonons of an electronic Wigner crystal
• Defects in Wigner crystals: fracton-elasticity duality and vacancy proliferation