2D condensate of electrons and holes in ultrathin MoTe${}_2$ photocells

Abstract

The electron-hole liquid, which features a macroscopic population of correlated electrons and holes, may offer a path to room temperature semiconductor devices that harness collective electronic phenomena. We report on the gas-to-liquid phase transition of electrons and holes in ultrathin molybdenum ditelluride photocells revealed through multi-parameter dynamic photoresponse microscopy (MPDPM). By combining rich visualization with comprehensive analysis of very large data sets acquired through MPDPM, we find that ultrafast laser excitation at a graphene-MoTe${}_2$-graphene interface leads to the abrupt formation of ring-like spatial patterns in the photocurrent response as a function of increasing optical power at T = 297 K. These patterns, together with extreme sublinear power dependence and picosecond-scale photocurrent dynamics, provide strong evidence for the formation of a two-dimensional electron-hole condensate.

References in corpus (11)

• The Raman Fingerprint of Graphene
• Observation of tightly bound trions in monolayer MoS2
• Exciton Binding Energy and Nonhydrogenic Rydberg Series in Monolayer WS2
• Observation of giant bandgap renormalization and excitonic effects in a monolayer transition metal dichalcogenide semiconductor
• Picosecond photoresponse in van der Waals heterostructures
• Indirect-to-direct band-gap crossover in few-layer MoTe${}_2$
• Photo-thermionic effect in vertical graphene heterostructures
• Ultrafast Response of Monolayer Molybdenum Disulfide (MoS2) Photodetectors
• Direct versus indirect band gap emission and exciton-exciton annihilation in atomically thin molybdenum ditelluride (MoTe${}_2$)
• Ultrafast photocurrent measurement of the escape time of electrons and holes from carbon nanotube PN junction photodiodes
• Theoretical phase diagram for the room temperature Electron-Hole Liquid in photo-excited quasi-2D monolayer MoS${}_2$

Cited by in corpus (18)

• Evidence of high-temperature exciton condensation in 2D atomic double layers
• Nonthermal pathways to ultrafast control in quantum materials
• Enhanced Light-Matter Interaction in Two-Dimensional Transition Metal Dichalcogenides
• Filtering the photoluminescence spectra of atomically thin semiconductors with graphene
• Near-unity light absorption in a monolayer WS2 van der Waals heterostructure cavity
• Collective Excitations in 2D Materials
• Consistent theory of self-bound quantum droplets with bosonic pairing
• Picosecond energy transfer in a transition metal dichalcogenide-graphene heterostructure revealed by transient Raman spectroscopy
• Harnessing Exciton-Exciton Annihilation in Two-Dimensional Semiconductors
• Quasiparticle Effective Mass of the Three-Dimensional Fermi Liquid by Quantum Monte Carlo
• Fermi Liquid Theory Sheds Light on "Hot" EHL in 1L-MoS${}_2$
• Mapping the intrinsic photocurrent streamlines through micromagnetic heterostructure devices
• Trapping Interlayer Excitons in van der Waals Heterostructures by Potential Arrays
• Phase diagram of electron-hole liquid in monolayer heterostructures based on transition metal dichalcogenides
• Dispersion forces between weakly disordered Van der Waals crystals
• Charge-separated electron-hole liquid in transition metal dichalcogenide heterostructures
• Exciton Mott Transition in Two-Dimensional Semiconductors
• Non-Equilibrium First-Order Exciton Mott Transition at Monolayer Lateral Heterojunctions Visualized by Ultrafast Microscopy