Room Temperature Terahertz Electroabsorption Modulation by Excitons in Monolayer Transition Metal Dichalcogenides
arXiv:2006.04786 · doi:10.1021/acs.nanolett.0c01134
Abstract
The interaction between off-resonant laser pulses and excitons in monolayer transition metal dichalcogenides is attracting increasing interest as a route for the valley-selective coherent control of the exciton properties. Here, we extend the classification of the known off-resonant phenomena by unveiling the impact of a strong THz field on the excitonic resonances of monolayer MoS. We observe that the THz pump pulse causes a selective modification of the coherence lifetime of the excitons, while keeping their oscillator strength and peak energy unchanged. We rationalize these results theoretically by invoking a hitherto unobserved manifestation of the Franz-Keldysh effect on an exciton resonance. As the modulation depth of the optical absorption reaches values as large as 0.05 dB/nm at room temperature, our findings open the way to the use of semiconducting transition metal dichalcogenides as compact and efficient platforms for high-speed electroabsorption devices.
40 pages, 11 figures
References in corpus (23)
- Optical Spectrum of MoS: Many-body Effects and Diversity of Exciton States
- Measurement of the optical dielectric function of transition metal dichalcogenide monolayers: MoS2, MoSe2, WS2 and WSe2
- The Computational 2D Materials Database: High-Throughput Modeling and Discovery of Atomically Thin Crystals
- Kramers-Kronig constrained variational analysis of optical spectra
- Valley-selective optical Stark effect in monolayer WS2
- Excitonic linewidth and coherence lifetime in monolayer transition metal dichalcogenides
- Photo-Induced Bandgap Renormalization Governs the Ultrafast Response of Single-Layer MoS2
- Ultrafast Generation of Pseudo-magnetic Field for Valley Excitons in WSe2 Monolayers
- Direct Measurement of Exciton Valley Coherence in Monolayer WSe
- Absorption of Light by Excitons and Trions in Monolayers of Metal Dichalcogenide MoS: Experiments and Theory
- Excitonic Dynamical Franz-Keldysh Effect
- Dynamical Franz-Keldysh effect
- Intervalley biexcitons and many-body effects in monolayer MoS2
- Dissociation of two-dimensional excitons in monolayer WSe2
- Large, valley-exclusive Bloch-Siegert shift in monolayer WS2
- Exciton Ionization, Franz-Keldysh and Stark Effects in Carbon Nanotubes
- Lecture Notes on the Theory of Open Quantum Systems
- Monitoring in real time the photon-dressing and undressing of quasiparticles from first principles time-resolved photoelectron spectroscopy
- Observation of exciton-exciton interaction mediated valley depolarization in monolayer MoSe
- Valley-dependent Exciton Fine Structure and Autler-Townes Doublets from Berry Phases in Monolayer Molybdenum Diselenide
- Valley-selective optical Stark effect probed by Kerr rotation
- Electroabsorption in MoS
- Systematic investigation of THz-induced excitonic Rabi splitting