相关论文: Non equilibrium anisotropic excitons in atomically…
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…
We present an electrostatic theory of band gap renormalization in atomically-thin semiconductors that captures the strong sensitivity to the surrounding dielectric environment. In particular, our theory aims to correct known band gaps, such…
We perform scanning photocurrent microscopy on WS2 ionic liquid-gated field effect transistors exhibiting high-quality ambipolar transport. By properly biasing the gate electrode we can invert the sign of the photocurrent showing that the…
Exciton-exciton interactions are key to understanding non-linear optical and transport phenomena in van der Waals heterobilayers, which emerged as versatile platforms to study correlated electronic states. We present a combined…
Anisotropic two-dimensional (2D) semiconductors recently have emerged as a promising platform for polarization-controlled Raman amplification. In this study, we probe energy-dependent resonant Raman scattering in few layer ReS2 under…
In a first-principles study based on density-functional theory and many-body perturbation theory we investigate the electronic properties and the optical excitations of ZrS$_2$ and HfS$_2$ monolayers and their van der Waals heterostructure.…
In semiconductor physics, many essential optoelectronic material parameters can be experimentally revealed via optical spectroscopy in sufficiently large magnetic fields. For monolayer transition-metal dichalcogenide semiconductors, this…
Strongly bound excitons confined in two-dimensional (2D) semiconductors are dipoles with a perfect in-plane orientation. In a vertical stack of semiconducting 2D crystals, such in-plane excitonic dipoles are expected to efficiently couple…
Two-dimensional transition metal dichalcogenides (2D TMDCs) are promising candidates for ultra-thin active nanophotonic elements due to the strong tunable excitonic resonances that dominate their optical response. Here we demonstrate…
Optically addressable spin impurities in crystals along with device engineering provide an attractive route to realizing quantum technologies in the solid state, but reconciling disparate emitter and host material constraints for a given…
The anisotropy of the electronic transition is an important physical property not only determining the materials' optical property, but also revealing the underlying character of the electronic states involved. Here we used…
Rhenium disulfide (ReS2) is a unique TMDC with a strong in-plane anisotropy and weak interlayer coupling. The pronounced anisotropy in the thermal conductivity observed in bulk ReS2 flakes (exceeding 60 nm) makes them valuable for…
Excitons are bosonic quasiparticles with a variety of applications in optoelectronics, photosyn thesis, and dissipationless informatics, and their lifetime can become sufficiently long to form a quantum condensate. While exciton…
We use a combined generalized spectroscopic ellipsometry and density functional theory approach to determine and analyze the anisotropic dielectric functions of an $\alpha$-Ga$_2$O$_3$ thin film. The sample is grown epitaxially by…
Excitons in a monolayer transition metal dichalcogenide (1L-TMD) are highly bound states characterized by a Rydberg-like spectrum of discrete energy levels. Among these, states with odd-parity are known as dark excitons due to selection…
Dipolar bosonic gases are currently the focus of intensive research due to their interesting many-body physics in the quantum regime. Their experimental embodiments range from Rydberg atoms to GaAs double quantum wells and van der Waals…
Few- and single-layer MoS2 host substantial densities of defects. They are thought to influence the doping level, the crystal structure, and the binding of electron-hole pairs. We disentangle the concomitant spectroscopic expression of all…
By combining electron energy-loss spectroscopy and state-of-the-art computational methods, we were able to provide an extensive picture of the excitonic processes in $1T$-HfS$_2$. The results differ significantly from the properties of the…
Geometrical confinement effect in exfoliated sheets of layered materials leads to significant evolution of energy dispersion with decreasing layer thickness. Molybdenum disulphide (MoS2) was recently found to exhibit indirect to direct gap…
In this study, we investigate excitonic properties of epitaxially grown WS2, which is of particular interest for various applications due to its potential for upscaling to wafer sized structures. Understanding the effect of the dielectric…