Related papers: Temperature dependence of ambipolar diffusion in s…
In bilayer systems electron-hole (e-h) pairs with spatially separated components (i.e., with electrons in one layer and holes in the other) can be condensed to a superfluid state when the temperature is lowered. This article deals with the…
Synchrotron infrared measurements were conducted over the range 100 to 8000 cm-1 on a self-doped LaxMnO3-d (x~~0.8) film. From these measurements we determined the conductivity, the effective number of free carriers, and the specific phonon…
Degenerate pump-probe reflectivity experiments have been performed on a single crystal of bismuth telluride (Bi$_2$Te$_3$) as a function of sample temperature (3K to 296K) and pump intensity using $\sim$ 50 femtosecond laser pulses with…
The investigation of the mechanical loss of different silicon flexures in a temperature region from 5 to 300 K is presented. The flexures have been prepared by different fabrication techniques. A lowest mechanical loss of $3\times10^{-8}$…
We study the effects of temperature on the band structure of the Bi$_2$Se$_3$ family of topological insulators using first-principles methods. Increasing temperature drives these materials towards the normal state, with similar…
Polarization-dependent scattering anisotropy of cylindrical nanowires has numerous potential applications in, for example, nanoantennas, photothermal therapy, thermophotovoltaics, catalysis, sensing, optical filters and switches. In all…
Heat transfer is a critical aspect of modern electronics, and a deeper understanding of the underlying physics is essential for building faster, smaller, and more powerful devices with an improved performance and efficiency. In such…
Future laser-interferometric gravitational wave detectors (GWDs) will potentially employ test mass mirrors from crystalline silicon and a laser wavelength of $1550\,\rm{nm}$, which corresponds to a photon energy below the silicon bandgap.…
Laser pulses with a duration of the order of femtoseconds lead to a strong excitation, heating and potentially to ablation of the irradiated material. During the time of strong excitation, the interaction of the atoms and thus the material…
This paper is devoted to the study of photothermal transformations in multilayered structures. As a modelled sample, porous silicon with a periodic distribution of the porosity was chosen. The spatial distribution of the optical properties…
Using direct atomic simulations, the vibration scattering time scales are characterized, and then the nature and the quantitative weight of thermal excitations are investigated in an example system Li2S from its amorphous solid state to its…
By independently engineering strain and composition, this work demonstrates and investigates direct band gap emission in the mid-infrared range from GeSn layers grown on silicon. We extend the room-temperature emission wavelength above ~4.0…
The ab-plane reflectance of Bi2Sr2CaCu2O(8+d) thin films was measured in the 30-25000 cm^(-1) range for one underdoped (Tc = 70 K), and one overdoped sample (Tc = 63 K) as a function of temperature (10-300 K). We find qualitatively similar…
We present results of molecular dynamics simulations of the electron system on the surface of liquid helium. The simulations are done for 1600 electrons with periodic boundary conditions. Electron scattering by capillary waves and phonons…
The analytical solutions of the equations describing impurity diffusion due to migration of nonequilibrium impurity interstitials were obtained for the impurity redistribution during ion implantation at elevated temperatures and for…
The evolution is presented of infrared transmission spectra of hydrogenated and chlorinated amorphous silicon films versus the chlorine concentration and the annealing temperature. As the chlorine content increases, an increase of the 2100…
Non-Fourier thermal transports have drawn significant attention for decades. Among them, the frequency dependent thermal conductivity has been extensively explored by pump-probe techniques, such as time-domain thermoreflectance, which is…
Understanding the ultrafast dynamics and transport of photoexcited carriers in topological insulators is crucial for the optical manipulation of spins and may shed light on the nature of topological excitons. Here we investigate…
Carrier and phonon dynamics in Bi2Se3 crystals are studied by a spatially resolved ultrafast pump-probe technique. Pronounced oscillations in differential reflection are observed with two distinct frequencies, and are attributed to coherent…
We study the temperature dependence of the orbital susceptibility of an excitonic insulator on the basis of a two-band model. It is shown that a drastic change (an anomalous enhancement) in susceptibility as a function of temperature occurs…