Ultrafast valley-selective coherent optical manipulation with excitons in WSe and MoS monolayers
arXiv:2204.00842 · doi:10.1038/s41699-023-00385-1
Abstract
Increasing the speed limits of conventional electronics requires innovative approaches to manipulate other quantum properties of electrons besides their charge. An alternative approach utilizes the valley degree of freedom in low-dimensional semiconductors. Here we demonstrate that the valley degeneracy of exciton energies in transition metal dichalcogenide monolayers may be lifted by coherent optical interactions on timescales corresponding to few tens of femtoseconds. The optical Stark and Bloch-Siegert effects generated by strong nonresonant circularly-polarized light induce valley-selective blue shifts of exciton quantum levels by more than 30 meV. We show these phenomena by studying the two most intensive exciton resonances in transiton metal dichalcogenide monolayers and compare the results to a theoretical model, which properly includes the Coulomb interaction and exciton dispersion. These results open the door for ultrafast valleytronics working at multiterahertz frequencies.
arXiv comment6 pages, 3 figures, published in npj 2D Materials and Applications
References in corpus (30)
- Atomically thin MoS2: A new direct-gap semiconductor
- Coupled spin and valley physics in monolayers of MoS2 and other group-VI dichalcogenides
- Control of valley polarization in monolayer MoS2 by optical helicity
- MoS_2 as an ideal material for valleytronics: valley-selective circular dichroism and valley Hall effect
- Valley contrasting physics in graphene: magnetic moment and topological transport
- Excitons in atomically thin transition metal dichalcogenides
- Optical Generation of Excitonic Valley Coherence in Monolayer WSe2
- k.p theory for two-dimensional transition metal dichalcogenide semiconductors
- Magnetic Control of Valley Pseudospin in Monolayer WSe2
- Valley Zeeman Effect in Elementary Optical Excitations of a Monolayer WSe2
- Dielectric screening in two-dimensional insulators: Implications for excitonic and impurity states in graphane
- Valley-selective optical Stark effect in monolayer WS2
- Valley susceptibility of an interacting two-dimensional electron system
- Ultrafast Generation of Pseudo-magnetic Field for Valley Excitons in WSe2 Monolayers
- Field-induced polarisation of Dirac valleys in bismuth
- Ultrafast Manipulation of Valley Pseudospin
- Thickness-Dependent Differential Reflectance Spectra of Monolayer and Few-Layer MoS2, MoSe2, WS2 and WSe2
- Control of Exciton Valley Coherence in Transition Metal Dichalcogenide Monolayers
- Valley Polarization in Si(100) at Zero Magnetic Field
- Large, valley-exclusive Bloch-Siegert shift in monolayer WS2
- Lightwave topology for strong-field valleytronics
- Floquet-Engineered Valleytronics in Dirac Systems
- Energy spectrum of two-dimensional excitons in a non-uniform dielectric medium
- Electronic Structure Theory of Strained Two-Dimensional Materials with Hexagonal Symmetry
- Tuning valley polarization in a WSe2 monolayer with a tiny magnetic field
- Probing and manipulating valley coherence of dark excitons in monolayer WSe
- Rydberg series of dark excitons and the conduction band spin-orbit splitting in monolayer WSe
- Valley-selective optical Stark effect probed by Kerr rotation
- A valleytronic diamond transistor: electrostatic control of valley-currents and charge state manipulation of NV centers
- Semiconductor Bloch equation analysis of optical Stark and Bloch-Siegert shifts in monolayers WSe and MoS
Cited by in corpus (9)
- Valley Polarization-Electric Dipole Interference and Nonlinear Chiral Selection Rules in Monolayer WSe
- Interaction induced AC-Stark shift of exciton-polaron resonances
- High harmonic generation in monolayer MoS2 controlled by resonant and near-resonant pulses on ultrashort time scales
- Exciton migration in two-dimensional materials
- Effects of Floquet Engineering on the Coherent Exciton Dynamics in Monolayer WS
- AC-Stark Spectroscopy of Interactions between Moiré Excitons and Polarons
- Real and Reciprocal Space Characterization of the 3-Dimensional Charge Density Wave in Quasi-1-Dimensional CuTe
- Ultrafast room-temperature valley manipulation in silicon and diamond
- Tracking the photoinduced dynamics of a dark excitonic state in single-layer WS via resonant Autler-Townes splitting