Related papers: Photoluminescence studies study of a phenyl-substi…
The photoluminescence (PL) of thermally evaporated Alq3 thin films has been studied in a few samples annealed and non-annealed and afterwards exposed to the laboratory atmosphere for over six years. It was found that the measured emission…
Electron-electron interactions in general lead to both ground state and excited state confinement. We show, however, that in phenyl-substituted polyacetylenes electron-electron interactions cause enhanced delocalization of quasiparticles in…
The optical properties of pentacene (PEN) and perfluoropentacene(PFP) thin films on various SiO2 substrates were studied using variable angle spectroscopic ellipsometry. Structural characterization was performed using X-ray reflectivity and…
In a pair of coupled donor-acceptor conjugated polymer chains, it is possible for an exciton photoexcited on either polymer to decay into a hole in the donor polymer's valence band and an electron in the conduction band of the acceptor…
Photo-physical and nonlinear-optical properties of a new amphiphilic conjugated polymer: hydroxylated pyridyl para-phenylene (Py-PhPPP) both in CH2Cl2 solution and in thin films have been investigated. By using Z-scan technique with…
Exciton plasmon polaritons have gained increasing interests over recent years due to their versatile properties emerging by the underlying light-matter coupling and making them potential candidates for new photonic applications. We have…
Thermally stable polymers have attracted a lot of interest due to their potential use as the active component in electronic, optical and optoelectronic applications, such as light-emitting diodes, light emitting electrochemical cells,…
We present a joint theory-experiment study on ultrafast photoluminescence from photoexcited graphene. Based on a microscopic theory, we reveal two distinct mechanisms behind the occurring photoluminescence: Besides the well-known incoherent…
Whereas their photophysics exhibits an intricate interplay of carriers with the lattice, most reports have so far relied on single compound studies. With the exception of variations of the organic spacer cations, the effect of constituent…
We report detailed temperature dependent photoluminescence (PL) spectra of pentacene (PEN), perfluoropentacene (PFP), and PEN:PFP mixed thin films grown on SiO2. PEN and PFP are particularly suitable for this study, since they are…
We report on the dynamics of photodegradation and subsequent recovery of two-photon fluorescence in a dye-doped polymer. The energy dependence suggests that photo-degradation is a linear process while recovery is entropic. Such recovery…
The thesis focuses on study of optical and photovoltaic properties of iso-type and aniso-type heterostructures based on photosensitive layers of organic semiconductors. The primary attention has been paid on determination of optimal…
We perform ab initio calculations of optical properties for a typical semiconductor conjugated polymer, poly-para-phenylenevinylene, in both isolated chain and crystalline packing. In order to obtain results for excitonic energies and…
The structural aspects of polyacrylamide thin films annealed at degradation threshold temperature have been studied as a function of annealing time using in situ X-ray reflectivity technique in vacuum. We observe significant decrease of…
Luminescence is the phenomenon investigated and applied in many disciplines of science and technique. Spectral and kinetic measurements of luminescence provide much information concerning the mechanism of luminescent devices. Better…
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…
We present photoluminescence studies as a function of temperature from a series of conjugated polymers and a conjugated molecule with distinctly different backbone conformations. The organic materials investigated here are: planar…
Layered III-chalcogenide compounds belong to a variety of layered crystals that can be implemented in van der Waals heterostructures. Here we report an optical study of the stability of two of these compounds: indium selenide (InSe) and…
Optical excitation of a chain in a polymer film may result in formation of an excimer, a superposition of on-chain excitons and charge-transfer excitons on the originally excited chain and a neighboring chain. The excimer emission is…
Polymer light-emitting devices were fabricated utilizing plasma polymerized thin films as emissive layers. These conjugated polymer films were prepared by RF Plasma Enhanced Chemical Vapor Deposition (PECVD) using naphthalene as monomer.…