An ultrafast two-dimensional visible/far-IR spectroscopy based on the IR/THz air biased coherent detection method and scanning the excitation frequencies is developed. The method allows the responses in the far-IR region caused by various electronic excitations in molecular or material systems to be observed in real time. Using the technique, the relaxation dynamics of the photo-excited carrier...

In this work, the compatibility and crystallinity of low density polyethylene (LDPE) and polybutene-1 (PB-1) blends were studied. Various blends of LDPE/PB-1 containing 5, 10 and 20 wt.% PB-1 were prepared in a corotating twin-screw extruder and characterized by scanning electron microscopy (SEM), shear oscillation rheology and wide-angle X-ray diffractometry (WAXD). A matrix-droplet morphology...

We consider the impact of the surface roughness and phonon induced relaxation on transport and spin characteristics in ultra-thin SOI MOSFET devices. We show that the regions in the momentum space, which are responsible for strong spin relaxation, can be efficiently removed by applying uniaxial strain. The spin lifetime in strained films can be improved by orders of magnitude, while the momentu...

conclusion in breast cancer after nac, the lesion t2 relaxation time was reduced in the responders, and this finding is potentially useful to assess the response to nac. results in 26 cases with nac, the mean lesion t2 relaxation time before nac was 81.34 ± 13.68 ms, compared with 64.50 ± 8.71 ms after nac. significant differences in the lesion t2 relaxation times existed between the pre- and p...

Silicon is a leading candidate material for spin-based devices, and two-dimensional electron gases s2DEGsd formed in silicon heterostructures have been proposed for both spin transport and quantum dot quantum computing applications. The key parameter for these applications is the spin relaxation time. Here we apply the theory of D’yakonov and Perel’ sDPd to calculate the electron spin resonance...

We use nonadiabatic mixed quantum/classical molecular dynamics to simulate recent time-resolved photoelectron spectroscopy (TRPES) experiments on the hydrated electron, and compare the results for both a cavity and a noncavity simulation model to experiment. We find that cavity-model hydrated electrons show an "adiabatic" relaxation mechanism, with ground-state cooling that is fast on the time ...

We present a femtosecond time-resolved optical spectroscopy (TRS) as an experimental tool to probe the changes in the low energy electronic density of states as a result of short and long range charge density wave order. In these experiments, a femtosecond laser pump pulse excites electron-hole pairs via an interband transition in the material. These hot carriers rapidly release their energy vi...

We report results of calculations of the effect of spin-orbit interaction on electron spin relaxation in a lateral quantum dot. Our study is motivated by puzzling results of high source-drain transport measurements of singlet-triplet transitions of two electrons in lateral and vertical devices that show a strong asymmetry as a function of the applied magnetic field. Using exact diagonalization ...

We present an empirical model for the electron energy relaxation time. It is based on Monte-Carlo simulation results and is applicable to all relevant diamond and zinc-blende structure semiconductors. The energy relaxation times are expressed as functions of the carrier and lattice temperatures, and in the case of semiconductor alloys, of the material composition. # 1999 Elsevier Science Ltd. A...

The understanding of spin dynamics and relaxation mechanisms in clean graphene, and the upper time and length scales on which spin devices can operate, are prerequisites to realizing graphene-based spintronic technologies. Here we theoretically reveal the nature of fundamental spin relaxation mechanisms in clean graphene on different substrates with Rashba spin-orbit fields as low as a few tens...