Related papers: Excitation Dynamics in Low Band Gap Donor-Acceptor…
We studied the recombination dynamics of charge carriers in organic bulk heterojunction solar cells made of the blend system poly(2,5-bis(3-dodecyl thiophen-2-yl) thieno[2,3-b]thiophene) (pBTCT-C12):[6,6]-phenyl-C61-butyric acid methyl…
The conversion of optical and electrical energy in novel materials is key to modern optoelectronic and light-harvesting applications. Here, we investigate the equilibration dynamics of photoexcited…
Bi possesses intriguing properties due to its large spin-orbit coupling, e.g. as a constituent of topological insulators. While its electronic structure and the dynamics of electron-phonon coupling have been studied in the past,…
Light harvesting as the first step in photosynthesis is of prime importance for life on earth. For a theoretical description of photochemical processes during light harvesting, spectral densities are key quantities. They serve as input…
A necessary first step in the development of technologies such as artificial photosynthesis is understanding the photoexcitation process within the basic building blocks of naturally-occurring light harvesting complexes (LHCs). The most…
Electron-hole (e-h) capture in luminescent conjugated polymers (LCPs) is modeled by the dissipative dynamics of a multilevel electronic system coupled to a phonon bath. Electroinjected e-h pairs are simulated by a mixed quantum state, which…
We developed a generalized model that considers light as energy contributed through the thermalization of excited carriers to generate excitation-intensity- and temperature-dependent phase diagrams. We find that the model replicates the…
Novel equations for the electric dipole polarizability $\alpha_{_{E1}}$ of low-lying excited states in atomic nuclei -- and the related $(-2)$ moment of the total photo-absorption cross section, $\sigma_{_{-2}}$ -- are inferred in terms of…
The efficiency of solution-processed colloidal quantum dot (QD) based solar cells is limited by poor charge transport in the active layer of the device, which originates from multiple trapping sites provided by QD surface defects. We apply…
The time dependence of device performance has been measured for photocells using blends containing the conjugated polymer, poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV) with two different functionalized C60 electron…
Understanding charge separation dynamics in organic semiconductor blends is crucial for optimizing the performance of organic photovoltaic solar cells. In this study, we explored the optoelectronic properties and charge separation dynamics…
Electroabsorption (EA) measurements can be used to identify the type of excitons contributing to the absorption spectra of semiconductors which have applications in optoelectronics. However, the inferences from the EA measurement greatly…
Covalently linked acene dimers are of interest as candidates for intramolecular singlet fission. We report many-electron calculations of the energies and wavefunctions of the optical singlets, the lowest triplet exciton and the…
Current-based deep level transient spectroscopy was used to study trap states in poly(3- hexylthiophene-2,5-diyl) (P3HT), [6,6]-phenyl-C61 butyric acid methyl ester (PCBM) and P3HT:PCBM blend. The obtained spectra showed traps of 87 meV…
In recent years, pi-conjugated polymers are attracting considerable interest in view of their light-dependent torsional reorganization around the pi-conjugated backbone, which determines peculiar light-emitting properties. Motivated by the…
We investigated photogeneration yield and recombination dynamics in blends of poly(3-hexyl thiophene) (P3HT) and poly[2-methoxy-5-(30,70-dimethyloctyloxy)-1,4-phenylenevinylene] (MDMO-PPV) with [6,6]- phenyl-C61 butyric acid methyl ester…
We study the photo-excitation dynamics of correlated band insulators, using non-equilibrium dynamical mean-field theory for the ionic Hubbard model. We find two distinct behaviors, depending on the ratio of the on-site interaction $U$ and…
Photogenerated excitonic ensembles confined in coupled GaAs quantum wells are probed by a complementary approach of emission spectroscopy and resonant inelastic light scattering. Lateral electrostatic trap geometries are used to create…
We have grown nitrogen-doped ZnO films grown by two kinds of epitaxial methods on lattice-matched ScAlMgO$_4$ substrates. We measured the photoluminescence (PL) of the two kinds of ZnO:N layers in the donor-acceptor-pair transition region.…
Relaxation processes following light excitation in semiconductors are key in materials-based quantum technology applications. These processes are broadly studied in atomically thin transition metal dichalcogenides (TMDs),…