Elucidating the decay mechanisms of photoexcited charge carriers is key to improving the efficiency of solar cells based on organo-lead halide perovskites. Here we investigate the spectral dependence (via above-, inter- and sub-bandgap optical excitations) of direct and trap-mediated decay processes in CH3NH3PbI3 using time resolved microwave conductivity (TRMC). We find that the total end-of-p...

We examine the momentum-dependent excitation spectra of indirect as well as direct resonant inelastic x-ray scattering (RIXS) processes in half-filled (extended) Hubbard rings. We determine the fundamental features of the ground-state RIXS response and discuss the experimental conditions that can allow for the low-energy part of these features to be distinguished in one-dimensional copper-oxide...

Strong localization effect in self-assembled InGaN quantum dots (QDs) grown by metalorganic chemical vapor deposition has been evidenced by temperature-dependent photoluminescence (PL) at different excitation power. The integrated emission intensity increases gradually in the range from 30 to 160 K and then decreases with a further increase in temperature at high excitation intensity, while thi...

The era of molecular medicine has ushered in the development of microscopic methods that can report molecular processes in thick tissues with high spatial resolution. A commonality in deep-tissue microscopy is the use of near-infrared (NIR) lasers with single- or multiphoton excitations. However, the relationship between different NIR excitation microscopic techniques and the imaging depths in ...

We have just concluded the study of radiation interaction with matter in which the basic mechanisms of charged particle, neutron and gamma interactions were discussed separately. A topic which makes use of all this information is the general problem of detection of nuclear radiation detection. Although this subject properly belongs to a course dealing with experimental aspects of applied nuclea...

Fluorescence correlation spectroscopy (FCS) could provide a more useful tool for intracellular studies and biological sample characterization if measurement times could be reduced. While an increase in laser power can enable an autocorrelation function (ACF) with adequate signal-to-noise to be acquired within a shorter measurement time, excitation saturation then leads to distortion of the ACF ...

Photo-initiated processes in molecules often involve complex situations where the induced dynamics is characterized by interplay of nuclear and electronic degrees freedom. The interaction molecule with an ultrashort laser pulse or coupling at a conical intersection (CoIn) induces coherent electron which subsequently modified motion. typically leads to fast decoherence but also, depending on sys...

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 utilize. Here we show that in prototype dimers present in a variety of photosynthetic antennae, efficient vibration-assisted energy transfer in the sub-picosecond timescale and at room temperature can manifest and benefit fr...

OBJECTIVE In response to the rapidly increasing interest in using human voice in cognitive brain research, a new method, semisynthetic speech generation (SSG), is presented for generation of speech stimuli. METHODS The method synthesizes speech stimuli as a combination of purely artificial processes and processes that originate from the natural human speech production mechanism. SSG first est...