相关论文: {\it Ab--initio} finite temperature excitons
Understanding the interplay between bright and dark exciton states is crucial for deciphering the luminescence properties of low-dimensional materials. The origin of the outstanding brightness of lead halide perovskites remains elusive.…
We study the thermodynamics of ultracold Bose atoms in optical lattices by numerically diagonalizing the mean-field Hamiltonian of the Bose-Hubbard model. This method well describes the behavior of long-range correlations and therefore is…
In current experiments with cold quantum gases in periodic potentials, interference fringe contrast is typically the easiest signal in which to look for effects of non-trivial many-body dynamics. In order better to calibrate such…
Mostly optical spectroscopies are used to investigate existence of excitons, Mott transitions and other exquisite excitonic condensed phases of matter. On the other hand, electrical signatures of excitons are hardly explored. Here we…
Room temperature detection of single quantum emitters has had a broad impact in fields ranging from biophysics to material science, photophysics, or even quantum optics. These experiments have exclusively relied on the efficient detection…
We propose an unconventional scheme of photoluminescence in a semiconductor thin film, where the nonlocal correlation between an excitonic wave and a light wave prominently enhances the exciton-light coupling beyond the long-wavelength…
Advancing the debate on quantum effects in light-initiated reactions in biology requires clear identification of non-classical features that these processes can exhibit and utilise. Here we show that in prototype dimers present in a variety…
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…
Excitons, namely neutral excitations in a system of electrons arising from the electron-hole interaction, are often essential to explain optical measurements in materials. They are governed by the Bethe-Salpeter equation, which can be cast…
Using a new time-resolved cathodoluminescence system dedicated to the UV spectral range, we present a first estimate of the radiative lifetime of free excitons in hBN at room temperature. This is carried out from a single experiment giving…
Future quantum computing architectures require electro-optic materials that maintain a strong, stable performance at cryogenic temperatures. In conventional electro-optic materials, large electro-optic coefficients are often confined to…
The exciton absorption coefficient is determined analytically for a semiconductor superlattice in crossed electric and magnetic fields, for the magnetic field being parallel and the electric field being perpendicular to the superlattice…
Polaritons, formed as a result of strong hybridization of matter with light, are promising for important applications including organic solar cells, optical logic gates, and qubits. Owing to large binding energies of Frenkel excitons…
We construct a many-body model Hamiltonian to capture how phonons renormalize exciton binding as a function of temperature. By using the GW approximation and density functional perturbation theory, we are able to parameterize this…
Thermal effects on the creation of particles under the influence of time-dependent boundary conditions are investigated. The dominant temperature correction to the energy radiated by a moving mirror is derived by means of response theory.…
Electroluminescence properties of epitaxially grown n-ZnO/p-GaN pn-heterojunctions are investigated as functions of applied bias and temperature. The study reveals the existence of indirect interfacial excitons at sufficiently low…
The optical properties of bulk ZrSiS nodal-line semimetal are theoretically studied within a many-body formalism. The G0W0 bands are similar to those calculated within the density functional theory, except near the {\Gamma} point; in…
Silicon nanocrystals are studied by time-resolved fluorescence spectroscopy. After laser excitation the bright and dark exciton ground state levels are populated at random, but subsequently the decay curves reveal a thermalization between…
Understanding the nature of the photoexcitation and ultrafast charge dynamics pathways in organic halide perovskite nanocubes and their aggregation into superlattices is key for the potential applications as tunable light emitters, photon…
In this paper we show experimental evidence of a few correlation regimes of a cold dipolar exciton fluid, created optically in a semiconductor bilayer heterostructure. In the higher temperature regime, the average interaction energy between…