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We present an energy-balance model of the electronic intersubband relaxation in optically excited n-type Ge/SiGe quantum wells with absorption resonance in the THz range. To this aim, the energy relaxation rates of the electron system due to interactions w ...
Photo-induced charge separation and charge transport are fundamental processes in many energy conversion techniques, where light is converted into chemical energy (PEC), into electrical energy (solar cells) or in the opposite sense if electrical energy is ...
The dynamics of the photoinduced commensurate-to-incommensurate charge density wave (CDW) phase transition in 4H(b)-TaSe2 are investigated by femtosecond electron diffraction. In the perturbative regime, the CDW re-forms on a 150-ps time scale, which is tw ...
We present a new type of metallic cathode, reaching quantum efficiency of 10(3). This value together with the estimated emittance, gives a brilliance of 2.8x10(13) A/m(2), making this cathode an excellent candidate for an ultrashort electron source. (C) 20 ...
Infrared (IR) reflectivity spectra of nominally pure Pb(Zr1-xTix)O-3 ceramics with different Ti/Zr concentration (x = 0.42-0.58) were measured and evaluated, along with the time-domain terahertz transmittance spectra in the temperature range 10 K-900 K. Th ...
The terahertz (THz) excitations in the quantum spin-ladder system Sr14Cu24O41 have been determined along the c axis using THz time-domain, Raman, and infrared spectroscopy. Low-frequency infrared and Raman active modes are observed above and below the char ...
We present the generation of high-power single-cycle terahertz (THz) pulses in the organic salt crystal 2-[3-(4-hydroxystyryl)-5.5-dimethylcyclohex-2-enylidene]malononitrile or OH1. Broadband THz radiation with a central frequency of 1.5 THz (lambda(c) = 2 ...
We present high-power single-cycle carrier-envelope phase locked THz pulses at a central frequency of 2.1 THz with MV/cm electric field strengths and magnetic field strengths beyond 0.3 T. The THz radiation is generated by optical rectification in an organ ...
Iodine added to iodide-based ionic liquids leads to extraordi- narily efficient charge transport, vastly exceeding that expect- ed for such viscous systems. Using terahertz time-domain spectroscopy, in conjunction with dc conductivity, diffusivity and visc ...