Related papers: Exciton states in monolayer MoSe2: impact on inter…
We present the micro-photoluminescence ($\mu$PL) and micro-reflectance contrast spectroscopy studies on thin films of MoSe2 with layer thicknesses ranging from a monolayer (1L) up to 5L. The thickness dependent evolution of the ground and…
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 report on the far-field photoluminescence intensity distribution of interlayer excitons in MoSe$_{2}$-WSe$_{2}$ heterostacks as measured by back focal plane imaging in the temperature range between 1.7 K and 20 K. By comparing the data…
We investigate valley exciton dynamics in MoSe2 monolayers in polarization- and time-resolved photoluminescence (PL) spectroscopy at 4K. Following circularly polarized laser excitation, we record a low circular polarization degree of the PL…
Monolayers (MLs) of MoS2 and WSe2 are 2D semiconductors with strong, direct optical transitions that are governed by tightly Coulomb bound eletron-hole pairs (excitons). The optoelectronic properties of these transition metal…
MoTe2 belongs to the semiconducting transition metal dichalcogenide family with some properties differing from the other well-studied members (Mo,W)(S,Se)2. The optical band gap is in the near infrared region and both monolayers and…
Interlayer excitons are observed coexisting with intralayer excitons in bi-layer, few-layer, and bulk MoSe2 single crystals by confocal reflection contrast spectroscopy. Quantitative analysis using the Dirac-Bloch-Equations provides…
In heterostructures consisting of different transition-metal dichalcogenide monolayers, a staggered band alignment can occur, leading to rapid charge separation of optically generated electron-hole pairs into opposite monolayers. These…
Excitons in thin layers of semiconducting transition metal dichalcogenides are highly subject to the strongly modified Coulomb electron-hole interaction in these materials. Therefore, they do not follow the model system of a two-dimensional…
The optical spectra of vertically stacked MoSe$_2$/WSe$_2$ heterostructures contain additional 'interlayer' excitonic peaks that are absent in the individual monolayer materials and exhibit a significant spatial charge separation in…
We report a photoluminescence (PL) and transient reflection spectroscopy study of exciton dynamics in monolayer transition transition-metal dichalcogenides (TMDs). PL saturation in monolayer MoSe2 occurs an excitation intensity more than…
Based on \emph{ab initio} theoretical calculations of the optical spectra of vertical heterostructures of MoSe$_2$ (or MoS$_2$) and WSe$_2$ sheets, we reveal two spin-orbit-split Rydberg series of excitonic states below the \textsl{A}…
Accurately described excitonic properties of transition metal dichalcogenide heterobilayers (HBLs) are crucial to comprehend the optical response and the charge carrier dynamics of them. Excitons in multilayer systems posses inter or…
We discuss here the effect of band nesting and topology on the spectrum of excitons in a single layer of MoS$_2$, a prototype transition metal dichalcogenide material. We solve for the single particle states using the ab initio based…
The photoluminescence (PL) in monolayer transition metal dichalcogenides (TMDs) is dominated by recombination of electrons in the conduction band with holes in the spin-orbit split valence bands, and there are two distinct emission features…
Excitons are vital in the photophysics of materials, especially in low-dimensional systems. The conceptual and quantitative understanding of excitonic effects in nonlinear optical (NLO) processes is more challenging compared to linear ones.…
We demonstrate electrical control of the A-exciton interband transition in mono- and few-layer $MoS_{2}$ crystals embedded into photocapacitor devices via the DC Stark effect. Electric field dependent low-temperature photoluminescence…
We present first-principles calculations of the optical response of monolayer molybdenum disulfide employing the GW-Bethe Salpeter equation (GW-BSE) approach including self-energy, excitonic, and electron-phonon effects. We show that…
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…
Monolayer transition-metal dichalcogenides are direct gap semiconductors with great promise for optoelectronic devices. Although spatial correlation of electrons and holes plays a key role, there is little experimental information on such…