Related papers: Calibrated Quantification of the Dark-Exciton Rese…
In two-dimensional transition metal dichalcogenide structures, the optical excitation of a bright exciton may be followed by the formation of a plethora of lower energy dark states. In these formation and relaxation processes between…
Photoluminescence intensity is widely used to infer exciton populations, yet the detected signal inherently convolves occupancy with radiative-rate modification and collection efficiency, making quantitative inversion vulnerable to pump and…
Exciton condensation--an interaction-driven, macroscopically coherent paired-fermion state--offers the prospect for dissipationless energy transport in solids, akin to that in superconductivity. Although their light effective mass and…
Monolayer transition metal dichalcogenides are a promising platform to investigate many-body interactions of excitonic complexes. In monolayer tungsten diselenide, the ground-state exciton is dark (spin-indirect), and the valley degeneracy…
Excitons with binding energies of a few hundreds of meV control the optical properties of transition metal dichalcogenide monolayers. Knowledge of the fine structure of these excitons is therefore essential to understand the optoelectronic…
The dynamics of exciton formation in transition metal dichalcogenides is difficult to measure experimentally, since many momentum-indirect exciton states are not accessible to optical interband spectroscopy. Here, we combine a tuneable…
Monolayer transition metal dichalcogenides (TMDs) exhibit a remarkably strong Coulomb interaction that manifests in tightly bound excitons. Due to the complex electronic band structure exhibiting several spin-split valleys in the conduction…
We study exciton radiative decay in a two-dimensional material, taking into account large thermal population in the non-radiative states, from which excitons are scattered into the radiative states by acoustic phonons. We find an analytical…
Coherent control of quantum systems has far-reaching implications in quantum engineering. In this context, coherent population trapping (CPT) involving dark resonances has played a prominent role, leading to a wealth of major applications…
The intricate interplay between optically dark and bright excitons governs the light-matter interaction in transition metal dichalcogenide monolayers. We have performed a detailed investigation of the "spin-forbidden" dark excitons in WSe2…
We show that a Bose-Einstein condensate consisting of dark excitons forms in GaAs coupled quantum wells at low temperatures. We find that the condensate extends over hundreds of micrometers, well beyond the optical excitation region, and is…
Quantum applications of solid state systems base upon generation and control of coherent electronic excitations. Prominent examples are exciton states in semiconductors excitable by photons. The high oscillator strength of electric-dipole…
Electric field-controlled, two-dimensional (2D) exciton dynamics in transition metal dichalcogenide monolayers is a current research focus in condensed matter physics. We have experimentally investigated the spectral and temporal properties…
Coulomb interactions in atomically thin materials are uniquely sensitive to variations in the dielectric screening of the environment, which can be used to control quasiparticles and exotic quantum many-body phases. A static approximation…
The monolayers of semiconducting transition metal dichalcogenides host strongly bound excitonic complexes and are an excellent platform for exploring many-body physics. Here we demonstrate a controlled kinetic manipulation of the…
Strong spatial confinement and highly reduced dielectric screening provide monolayer transition metal dichalcogenides (TMDCs) with strong many-body effects, thereby possessing optically forbidden excitonic states (i.e., dark excitons) at…
A functional heterostructure is central to integrated circuitry in quantum photonics, optoelectronics, neuromorphic computing, spintronics, and straintronics. Recently, heterostructures combining 2D magnets and nonmagnetic transition metal…
We performed spin-, time- and angle-resolved extreme ultraviolet photoemission spectroscopy (STARPES) of excitons prepared by photoexcitation of inversion-symmetric 2H-WSe$_2$ with circularly polarized light. The very short probing depth of…
Electric dipole radiation can be controlled by coherent optical feedback, as has previously been studied by modulating the photonic environment for point dipoles placed both in optical cavities and near metal mirrors. In experiments…
The exciton recombination and spin dynamics in (In,Al)As/AlAs quantum dots (QDs) with indirect band gap and type-I band alignment are studied. The negligible (less than $0.2~\mu$eV) value of the anisotropic exchange interaction in these QDs…