相关论文: Exciton mapping at subwavelength scales in two-dim…
Many of the fundamental optical and electronic properties of atomically thin transition metal dichalcogenides are dominated by strong Coulomb interactions between electrons and holes, forming tightly bound atom-like excitons. Here, we…
Reflectance and magneto-reflectance experiments together with theoretical modelling based on the $\mathbf{k\cdot p}$ approach have been employed to study the evolution of direct bandgap excitons in MoS$_2$ layers with a thickness ranging…
Double layer systems where one layer has electrons and the holes are in a parallel layer a distance d away are expected to undergo excitonic condensation at low temperature. This excitonic condensate is traditionally described by a…
With the development of affordable aberration-correctors, analytical scanning transmission electron microscopy (STEM) studies of complex interfaces can now be conducted at high spatial resolution at laboratories worldwide. Energy-dispersive…
We have investigated the electronic excitations in bulk 2H-MoS2 using electron energy-loss spectroscopy. The electron energy-loss spectra in the {\Gamma}M and {\Gamma}K directions were measured for various momentum transfer values. The…
An exciton theory for quasi-one dimensional organic materials is developed in the framework of the Su-Schrieffer-Heeger Hamiltonian augmented by short range extended Hubbard interactions. Within a strong electron-electron correlation…
Efficient nonlinear wave mixing is of paramount importance for a wide range of applications. However, weak optical nonlinearities pose significant challenges for accessing nonlinear light-matter interaction in compact systems. Here, we…
Moir\'e superlattices open an unprecedented opportunity for tailoring interactions between quantum particles and their coupling to electromagnetic fields. Strong superlattice potential generates moir\'e minibands of excitons -- bound pairs…
Tuning the electronic properties of a material by subjecting it to strain constitutes an important strategy to enhance the performance of semiconducting electronic devices. Using local strain, confinement potentials for excitons can be…
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…
Exciton-exciton interactions are fundamental to the light-emitting properties of semiconductors, influencing applications from lasers to quantum light sources. In this study, we investigate the spectroscopic signatures and binding energy of…
The advance in designing arrays of ultrathin two-dimensional optical nano-resonators, known as metasurfaces, is currently enabling a large variety of novel flat optical components. The remarkable control over the electromagnetic fields…
The {\AA}ngstr\"om-sized probe of the scanning transmission electron microscope can visualize and collect spectra from single atoms. This can unambiguously resolve the chemical structure of materials, but not their isotopic composition.…
In this work, we show that spectroscopic ellipsometry can be combined with photoemission spectroscopy to obtain complete interface band diagrams of non-ideal semiconductor heterointerfaces, such as interfaces between thin-film…
Semi-metallic graphene and semiconducting monolayer transition metal dichalcogenides (TMDCs) are the two-dimensional (2D) materials most intensively studied in recent years. Recently, black phosphorus emerged as a promising new 2D material…
Excitons, or bound electron-hole pairs, play a crucial role in the optical response of monolayer, 2H-phase transition-metal dichalcogenides (TMDs). They hold significant promise for the development of novel quantum opto-electronic devices…
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.…
The possibility of spatially resolving the optical properties of atomically thin materials is especially appealing as they can be modulated at the micro- and nanoscale by reducing their thickness, changing the doping level or applying a…
The ground state of two-dimensional (2D) electron systems with equal low densities of electrons and holes in nearby layers is an exciton fluid. We show that a reservoir for excitons can be established by contacting the two layers separately…
Atomically thin two-dimensional crystals have revolutionized materials science. In particular, monolayer transition metal dichalcogenides promise novel optoelectronic applications, due to their direct energy gaps in the optical range. Their…