相关论文: Nonlinear light absorption in colloidal CdSe/CdS n…
We aim to clarify the role that absorption plays in nonlinear optical processes in a variety of metallic nanostructures and show how it relates to emission and conversion efficiency. We define a figure of merit that establishes the…
Saturation effects affecting absorption and fluorescence spectra of an atomic vapor confined in an Extremely Thin Cell (cell thickness $L < 1 \mu m$) are investigated experimentally and theoretically. The study is performed on the $D_{2}$…
We study the nonequilibrium exciton-polariton condensation in 1D to 0D and 1D to 2D junctions by means of non-resonant spectroscopy. The shape of our potential landscape allows to probe the resonant transmission of a propagating condensate…
In atomically thin semiconductors based on transition metal dichalcogenides, photoexcitation can be used to generate high densities of electron-hole pairs. Due to optical nonlinearities, which originate from Pauli blocking and many-body…
Exciton luminescence of a CdSe quantum dot (QD) inserted in a ZnSe nanowire is strongly influenced by the dark exciton states. Because of the small size of these QDs (2-5nm), exchange interaction between hole and electron is highly enhanced…
We theoretically study nonlinear optics of excitons under intense THz irradiation. In particular, the linear near infrared absorption and resonantly enhanced nonlinear sideband generation are described. We predict a rich structure in the…
The photoluminescence spectra of spherical CdTe nanocrystals with zincblende structure are studied by size-selective spectroscopic techniques. We observe a resonant Stokes shift of 15 meV when the excitation laser energy is tuned to the red…
The absorption spectra of single-layer GaSe and GaTe in the hexagonal phase feature exciton peaks with distinct polarization selectivity. We investigate these distinct features from first-principle calculations using the GW-BSE formalisms.…
Zinc-blende CdSe semiconducting nanoplatelets (NPL) show outstanding quantum confinement properties thanks to their small, atomically-controlled, thickness. For example, they display extremely sharp absorption peaks that make them very…
We present an experimental demonstration of strong coupling between a surface plasmon propagating on a planar silver substrate, and the lowest excited state of CdSe nanocrystals. Variable-angle spectroscopic ellipsometry measurements…
We review the studies of a wide range of optical phenomena resulting from near-field coupling between excitons and localized surface plasmon-polaritons in hybrid nanostructures. Modern physical approaches and theoretical models reported…
We study exciton-polariton nonlinear optical fluids in a high momentum regime for the first time. Defects in the fluid develop into dark solitons whose healing length decreases with increasing density. We deduce interaction constants for…
We report on polarization-resolved resonant photoluminescence (PL) spectroscopy of bright (spin-1) and dark (spin-2) excitons in colloidal CdSe nanocrystal quantum dots. Using high magnetic fields to 33 T, we resonantly excite (and…
Phonon spectra of CdSe nanoplatelets (2-6 ML) with the zinc-blende structure were calculated from first principles within the density-functional theory. It turned out that the Lamb modes in nanoplatelets are in fact optical rather than…
Exciton-polaritons - hybrid light-matter quasiparticles - can undergo Bose-Einstein-like condensation at elevated temperatures owing to their lower effective mass. This becomes even more pronounced in the context of molecular polariton…
The interaction between excitons and phonons in semiconductor nanocrystals plays a crucial role in the exciton energy spectrum and dynamics, and thus in their optical properties. We investigate the exciton2 phonon coupling in giant-shell…
This thesis studies light-matter interactions in strong and weak coupling regimes. In the first part, we study the formation and propagation of exciton-polariton condensates in different microcavities in the strong coupling regime.…
Exciton energy structure and population dynamics in a wide CdTe/CdZnTe quantum well are studied by spectrally-resolved pump-probe spectroscopy. Multiple excitonic resonances in reflectance spectra are observed and identified by solving…
Cs-based semiconductors like $\mathrm{Cs_3Sb}$ and $\mathrm{Cs_2Te}$ are currently used as photocathodes in particle accelerators. Their performance as electron sources critically depends on their interaction with intense laser sources. In…
Energy absorption of xenon clusters embedded in helium nanodroplets from strong femtosecond laser pulses is studied theoretically. Compared to pure clusters we find earlier and more efficient energy absorption in agreement with experiments.…