相关论文: Excitons and Excitonic Molecules in Mixed $Zn(P_{1…
Excitonic absorption, reflection and photoluminescence spectra of mixed Zn(P_{1-x}As_{x})_{2}crystals over the full range of x (0 < x < 1) and Zn_{1-x}Cd_{x}P_{2} crystals at 0 < x < 0.05 have been studied at low temperatures (1.8 K). The…
Photoluminescence from bulk HfS$_2$ grown by the chemical vapor transport method is reported. A series of emission lines is apparent at low temperature in the energy range of 1.4 - 1.5 eV. Two groups of the observed excitonic transitions…
Hybrid perovskite thin films have demonstrated impressive performance for solar energy conversion and optoelectronic applications. However, further progress will benefit from a better knowledge of the intrinsic photophysics of materials.…
The absorption and emission spectra of silicon nanocrystals up to 1 nm diameter including geometry optimization and the many-body effects induced by the creation of an electron-hole pair have been calculated within a first-principles…
We study the theory of itinerant-hole photoluminescence of two-dimensional electron systems in the regime of the magnetically induced Wigner crystal. We show that the exciton recombination transition develops structure related to the…
Scintillation properties of $({\rm Zn}_{0.9} {\rm Pb}_{0.1})({\rm W}_{0.9} {\rm Mo}_{0.1}){\rm O}_4$ and $({\rm Zn}_{0.9} {\rm Cd}_{0.1})({\rm W}_{0.9} {\rm Mo}_{0.1}){\rm O}_4$ mixed crystals with doping of ${\rm Eu, Sm, Pr, Ce, Sc, Yt}$…
We revisit low-temperature optical spectra of transition-metal dichalcogenide monolayers and point to a possible crystallization of electrons (or holes) at low to moderate charge densities. To calculate the excitonic spectra under such…
The magnetic field dependence of photoabsorption provides direct insights into the band structure of semiconductors. It is perhaps surprising that there is a large discrepancy between electron, hole, and reduced mass reported in the recent…
Optical and magneto-optical properties of ZnMnO films grown at low temperature by Atomic Layer Deposition are discussed. A strong polarization of excitonic photoluminescence is reported, surprisingly observed without splitting or spectral…
Linear and non-linear spectroscopies are powerful tools used to investigate the energetics and dynamics of electronic excited states of both molecules and crystals. While highly accurate \emph{ab initio} calculations of molecular spectra…
The excitonic luminescence of an isolated polydiacetylene polymer chain in its monomer matrix is studied by micro-photoluminescence. These chains behave as perfect 1D excitonic systems with the expected 1/sqrt{E} density of states between 5…
The present paper deals with the results of a research work on the optical properties of colloidal InP/ZnS nanocrystals stabilized with a heterobifunctional polyvinylpyrrolidone polymer. We have analyzed the absorption and photoluminescence…
Absorption and emission of pristine-like semiconducting monolayers of BN, AlN, GaN, and InN are here systematically studied by ab-initio methods. We calculate the absorption spectra for in-plane and out-of-plane light polarization including…
We have performed first-principles calculations to study optical absorption spectra of doped graphene with many-electron effects included. Both self-energy corrections and electron-hole interactions are reduced due to the enhanced screening…
We measure temperature-dependent one-photon and two-photon induced photoluminescence from (CH3NH3)PbBr3 single crystals cleaved in ultrahigh vacuum. An approach is presented to extract absorption spectra from a comparison of both…
A phenomenological theory of luminescence properties of one-dimensional resonant photonic crystals is developed within the framework of classical Maxwell equations with fluctuating polarization terms representing non-coherent sources of…
Excitons are neutral excitations that are composed of electrons and holes bound together by their attractive Coulomb interaction. The electron and the hole forming the exciton also interact with the underlying atomic lattice, and this…
In this paper, we simulate the linear absorption spectra of the MePTCDI and PTCDA crystals. The basic Hamiltonian describes the Frenkel excitons and charge-transfer excitons mixing in the molecular stack (point group C_i) and their linear…
We report on amplified emission in polycrystalline ZnO below 100K. At 6K emission is due to free exciton FXn=1 A (3.378 eV), bound exciton D1XA (3.347 eV), donor acceptor pair DAP (3.275 eV) and longitudinal phonon replica of free excitons…
The optical properties of molecular crystals are largely determined by the excitonic coupling of neighboring molecules. This coupling is extremely sensitive to the arrangement of adjacent molecular units, as their electronic interaction is…