europium (eu) doped zno microsphere based nano-sheets were synthesized through hydrothermal method. effects of different concentrations of europium on structural and optical properties of zno nano-sheets were investigated in detail. prepared un-doped and eu-doped zno samples were characterized using x-ray diffraction (xrd), energy dispersive x-ray spectroscopy (edx), scanning electron microscop...

The competition between exciton dissociation and charge transport in organic solar cells comprising poly(3-hexylthiophene) [P3HT] and phenyl-C61-butyric acid methyl ester [PCBM] is investigated by correlated scanning confocal photoluminescence and photocurrent microscopies. Contrary to the general expectation that higher photoluminescence quenching is indicative of higher photocurrent, microsca...

We present photoluminescence (PL) spectroscopy measurements of single-layer MoSe2 as a function of uniform uniaxial strain. A simple clamping and bending method is described that allows for application of uniaxial strain to layered, 2D materials with strains up to 1.1% without slippage. Using this technique, we find that the electronic band gap of single layer MoSe2 can be reversibly tuned by -...

Poly(3-hexylthiophene) (P3HT) nanoparticles (NPs) were prepared by a reprecipitation method. Hydrothermal processing applied external pressure to the pristine P3HT NPs at temperatures ranging from 60 to 150 °C. Optical absorption and photoluminescence (PL) spectra for the hydrothermally treated P3HT NPs varied markedly with the processing temperature. With increasing treatment temperature, the ...

Recent experiments on two-dimensional exciton systems have shown that excitons collect in shallow in-plane traps. We find that Bose condensation in a trap results in a dramatic change of the exciton photoluminescence (PL) angular distribution. The long-range coherence of the condensed state gives rise to a sharply focused peak of radiation in the direction normal to the plane. By comparing the ...

Functionalization of light-emitting poly(3-methylthiophene) (P3MT) nanowires (NWs) with probe-DNA (p-DNA) and their label-free recognition of target-DNA (t-DNA) were correlated quantitatively with both the photoluminescence (PL) color and intensity of P3MT NWs.

Hybrid structures of few or single quantum dots (QDs) coupled to single optical antennas are of prime interest for nano-optical research. The photoluminescence (PL) signal from single nanoemitters, such as QDs, can be enhanced, and their emission characteristics modified, by coupling them to plasmonic nanostructures. Here, a self-aligned technique for placing nanoscale QDs with about 10 nm late...

Strain-engineering of two-dimensional (2D) transition metal dichalcogenides (TMDs) has great potential to alter their electronic and optical properties. Thus far, experimental studies of the straining effects in 2D TMDs primarily focused on the static property measurements at room temperature. However, low-temperature and temperature-dependence studies are essential in understanding the underly...

Quantum and dielectric confinement effects in 2D hybrid perovskites create excitons with a binding energy exceeding 150 meV. We exploit the large exciton binding energy to study exciton and carrier dynamics as well as electron-phonon coupling in hybrid perovskites using absorption and photoluminescence (PL) spectroscopies. At temperatures below 75 K, we resolve splitting of the excitonic absorp...

The authors report the growth of ZnSe/ZnSeTe superlattice nanotips on oxidized Si(100) substrate. It was found the nanotips exhibit mixture of cubic zinc-blende and hexagonal wurtzite structures. It was also found that photoluminescence intensities observed from the ZnSe/ZnSeTe superlattice nanotips were much larger than that observed from the homogeneous ZnSeTe nanotips. Furthermore, it was fo...