Related papers: Carrier density driven lasing dynamics in ZnO nano…
We study the effect of localized Joule heating on the mechanical properties of doubly clamped nanowires under tensile stress. Local heating results in systematic variation of the resonant frequency; these frequency changes result from…
The observed correlation of oxygen vacancies and room temperature ferromagnetic ordering in Co doped ZnO1-o nanoparticles reported earlier (Naeem et al Nanotechnology 17, 2675-2680) has been further explored by transport and optical…
The dynamics of the charge ordered (CO) state under non-equilibrium conditions created by strong dc-electric field (~106 V/cm) and photo-illumination with short (~ 6 ns) laser pulses is investigated in Bi1-xCaxMnO3 (x > 0.5) epitaxial…
By using the pulsed-laser-ablation technique, we have successfully grown the La$_{3}$Ni$_{2}$O$_{7-\delta}$ thin films with $c$-axis orientation perpendicular to the film surface. X-ray diffraction shows that the (00l) peaks can be well…
We demonstrate edge-emitting exciton-polariton (polariton) lasing from 5 to 300 K and amplification of non-radiative guided polariton modes within ZnO waveguides. The mode dispersion below and above the lasing threshold is directly measured…
Combining time-dependent density functional calculations for electrons with molecular dynamics simulations for ions, we investigate the dynamics of excited carriers in a (3,3) carbon nanotube at different temperatures. Following an hv=6.8…
We study experimentally and theoretically polarization-dependent luminescence from an ensemble of quantum-dot-like nanostructures with a very large in-plane shape anisotropy (quantum dashes). We show that the measured degree of linear…
As high-average power ultrafast lasers become increasingly available for nonlinear conversion, the temperature dependence of the material properties of nonlinear crystals becomes increasingly relevant. Here, we present temperature-dependent…
Hot carrier dynamics in a dispersionless plasmonic structures over a broad wavelength are studied by pump-probe measurements with 45 fs time resolution. The role of direct excited as well as plasmon generated hot carriers on low energy…
A unified theoretical description is developed for the formation of an ionized filament channel in a dense-gas medium and the evolution of electronic degrees of freedom in this channel in the laser pulse wake, as illustrated on an example…
This research investigates the structural, topological, electrical and optical properties of pulsed laser deposited polycrystalline BiFeO3 thin films on silicon and glass substrate at varying deposition temperatures ranging from 400 degC to…
Stimulated surface- and edge-emission were investigated for ZnO thin films grown epitaxially by pulsed laser deposition. The lasing threshold was 0.32 MW/cm2 for surface pumping and 0.5 MW/cm2 for edge pumping, which is significantly lower…
We propose a theory of low temperature thermal transport in nano-wires in the regime where a competition between phonon and flexural modes governs the relaxation processes. Starting with the standard kinetic equations for two different…
We present picosecond-resolution streaked K-shell spectra from 400 nm-diameter nickel nanowire arrays, demonstrating the ability to generate large volumes of high energy density plasma when combined with the longer pulses typical of the…
We performed terahertz magneto-optical spectroscopy of FeSe thin film to elucidate the charge carrier dynamics. The measured diagonal (longitudinal) and off-diagonal (Hall) conductivity spectra are well reproduced by two-carrier Drude…
We investigate, from a theoretical perspective, photo-emission of electrons induced by ultra-short infrared pulses covering only a few photon cycles. In particular, we investigate the impact of the Carrier-Envelope Phase (CEP) of the laser…
In monolayer MoS2 optical transitions across the direct bandgap are governed by chiral selection rules, allowing optical valley initialization. In time resolved photoluminescence (PL) experiments we find that both the polarization and…
We propose that the observed low density ``insulating'' phase of a 2D semiconductor system, with the carrier density being just below ($n < n_c$) the so-called critical density where the derivative of resistivity changes sign at low…
Inelastic electron tunneling and surface-enhanced optical spectroscopies at the molecular scale require cryogenic local temperatures even under illumination - conditions that are challenging to achieve with plasmonically resonant metallic…
I explore the thermal evolution and ionization states in gas cooling from an initially hot state in the presence of external photoionizing radiation. I compute the equilibrium and nonequilibrium cooling efficiencies, heating rates, and ion…