Related papers: Observation of intervalley biexcitonic optical Sta…
Active control over strong optical nonlinearity in solid-state systems is central to unlocking exotic many-body phenomena and scalable photonic devices. While exciton-polaritons in transition metal dichalcogenides (TMDs) offer a promising…
Electrons in 2-dimensional crystals with a honeycomb lattice structure possess a new valley degree of freedom (DOF) in addition to charge and spin. Each valley is predicted to exhibit a Hall effect in the absence of a magnetic field whose…
Monolayer transition metal dichalcogenides, known for exhibiting strong excitonic resonances, constitute a very interesting and versatile platform for investigation of light-matter interactions. In this work we report on a strong coupling…
We investigate the effect on disorder potential on exciton valley polarization and valley coherence in monolayer WSe2. By analyzing polarization properties of photoluminescence, the valley coherence (VC) and valley polarization (VP) is…
van der Waals stacking of two-dimensional (2D) materials offers a powerful platform for engineering material interfaces with tailored electronic and optical properties. While most van der Waals multilayers have featured inorganic…
We start with the silicene or germanene single-particle Hamiltonian in buckled 2D hexagonal lattices expressed in terms of Dirac matrices in the Weyl basis. The Hamiltonian of these systems comprises of the Dirac kinetic energy, a mass gap…
By pumping nonresonantly a MoS$_2$ monolayer at $13$ K under a circularly polarized cw laser, we observe exciton energy redshifts that break the degeneracy between B excitons with opposite spin. The energy splitting increases monotonically…
The semiconducting single-layer transition metal dichalcogenides have been identified as ideal materials for accessing and manipulating spin- and valley-quantum numbers due to a set of favorable optical selection rules in these materials.…
Electrons in monolayer transition metal dichalcogenides (TMDs) possess both the valley and spin degree of freedom. These internal quantum degrees of freedom have provided an ideal laboratory for exploring both new physical phenomena and…
Studies of excitonic transport in transition metal dichalcogenide monolayers have attracted increasing interest in recent years in order to develop nano-optoelectronic devices made with 2D materials. These studies began with low to moderate…
Transition metal dichalcogenides have been the primary materials of interest in the field of valleytronics for their potential in information storage, yet the limiting factor has been achieving long valley decoherence times. We explore the…
Heterostructures comprising different monolayer semiconductors provide a new system for fundamental science and device technologies, such as in the emerging field of valleytronics. Here, we realize valley-specific interlayer excitons in…
Spatial heterogeneity and phase competition are hallmarks of strongly-correlated materials, promising tunable functionality on the nanoscale. Light-induced switching of a correlated insulator to a metallic state is well established.…
Here, the underlying mechanisms behind valley de-polarization is investigated in chemical vapor deposited 1L-MoS$_{2}$. Temperature dependent polarization resolved photoluminescence spectroscopy was carried out on as-grown, transferred and…
We report a rare atom-like interaction between excitons in monolayer WS2, measured using ultrafast absorption spectroscopy. At increasing excitation density, the exciton resonance energy exhibits a pronounced redshift followed by an…
Van der Waals heterostructures of two-dimensional transition metal dichalcogenides provide a unique platform to engineer optoelectronic devices tuning their optical properties via stacking, twisting, or straining. Using ab initio Many-Body…
Monolayers of transition metal dichalcogenides (TMDCs) exhibit an exceptionally strong Coulomb interaction between charge carriers due to the two-dimensional carrier confinement in connection with weak dielectric screening. High densities…
The optical control of spin- and valley-selective gapless states in two-dimensional materials presents new opportunities for next-generation spintronic and valleytronic technologies. In this work, we study monolayer jacutingaite…
Due to degeneracies arising from crystal symmetries, it is possible for electron states at band edges ("valleys") to have additional spin-like quantum numbers. An important question is whether coherent manipulation can be performed on such…
We have investigated the steady-sate valley polarization and valley coherence of encapsulated MoS2 monolayer as a function of the temperature and the power density with a continuous wave laser excitation. Both valley polarization and…