Related papers: Hexcitons and oxcitons in monolayer WSe$_2$
The high-quality structures containing semiconducting transition metal dichalcogenides (S-TMDs) monolayer (MLs) required for optical and electrical studies are achieved by their encapsulation in hexagonal BN (hBN) flakes. To examine the…
Two-dimensional dilute magnetic semiconductors has been recently reported in semiconducting transition metal dichalcogenides by the introduction of spin-polarized transition metal atoms as dopants. This is the case of vanadium-doped WS$_2$…
Interactions among a collection of particles generate many-body effects in solids resulting in striking modifications of material properties. The heavy carrier mass that yields strong interactions and gate control of carrier density over a…
Two-dimensional moir\'e materials provide a highly tunable platform to investigate strongly correlated electronic states. Such emergent many-body phenomena can be optically probed in moir\'e systems created by stacking two layers of…
Momentum-indirect excitons composed of electrons and holes in different valleys define optoelectronic properties of many semiconductors, but are challenging to detect due to their weak coupling to light. The identification of an excitons'…
In crystals, energy band extrema in momentum space can be identified by their valley index. The internal quantum degree of freedom associated with valley pseudospin indices can act as a useful information carrier analogous to electronic…
Monolayer WSe$_2$ hosts a series of exciton Rydberg states denoted by the principal quantum number n = 1, 2, 3, etc. While most research focuses on their absorption properties, their optical emission is also important but much less studied.…
Two dimensional materials and their heterostructures constitute a promising platform to study correlated electronic states as well as many body physics of excitons. Here, we present experiments that unite these hitherto separate efforts and…
We report dissipative dynamics of two valley excitons residing in the $K$ and $K^\prime$-valleys of bare WSe$_2$ monolayer and the one being integrated into a bimodal optical cavity. In the former, only when the exciton-field detunings in…
We present here a formalism based on time-dependent density-functional theory (TDDFT) to describe characteristics of both intra- and inter-valley excitons in semiconductors, the latter of which had remained a challenge. Through the usage of…
Single photons emitters (SPEs) are key components in quantum information applications and are commonly generated in 2D materials by inhomogeneous strain engineering. Here, we report an alternative approach that involves a 2D…
Low temperature and polarization resolved magneto-photoluminescence experiments are used to investigate the properties of dark excitons and dark trions in a monolayer of WS$_2$ encapsulated in hexagonal BN (hBN). We find that this system is…
We show that band topology can dramatically change the photophysics of two-dimensional (2D) semiconductors. For systems in which states near the band extrema are of multiple orbitals character and the spinors describing the orbital…
Bound electron-hole excitonic states are generally not expected to form with charges of negative effective mass. We identify such excitons in a single layer of the semiconductor WSe2, where they give rise to narrow-band upconverted…
A three-step process was developed for growing high-quality, optically uniform WSe2 monolayers by molecular beam epitaxy (MBE) with advantage of using hexagonal boron nitride (hBN). The process was optimized to maximize the efficiency of…
Coulomb bound electron-hole pairs, excitons, govern the optical properties of semi-conducting transition metal dichalcogenides like MoS$_2$ and WSe$_2$. We study optical transitions at the K-point for 2H homobilayer MoS$_2$ in Density…
We investigate the origin of emission lines apparent in the low-temperature photoluminescence spectra of $n$-doped WS$_2$ monolayer embedded in hexagonal BN layers using external magnetic fields and first-principles calculations. Apart from…
Recent optical studies of monolayer transition metal dechalcogenides have demonstrated that their excitonic absorption feature splits into two widely separated peaks at finite carrier densities. The additional peak is usually attributed to…
The study of exciton-polarons has offered profound insights into the many-body interactions between bosonic excitations and their immersed Fermi sea within layered heterostructures. However, little is known about the properties of exciton…
We present optical spectroscopy (photoluminescence and reflectance) studies of thin layers of the transition metal dichalcogenide WSe2, with thickness ranging from mono- to tetra-layer and in the bulk limit. The investigated spectra show…