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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 ...
We propose a definition for the dipole of an individual molecule in a molecular solid or fluid. This problem is currently dealt with by partitioning-according to some prescription-the continuous electron density of the condensed phase. Instead, here we foc ...
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 ...
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 concept and analysis of a terahertz (THz) frequency-reconfigurable antenna using graphene are presented. The antenna exploits dipole-like plasmonic resonances that can be frequency-tuned on large range via the electric field effect in a graphene stack. ...
The present work is devoted to the study of the dynamics of multi-photon processes in semiconductor heterostructures. A time-dependent description is important for understanding in detail the transient response of semiconductors excited by ultrashort optic ...
The impact ionization of excitonic states is studied in epitaxial GaN films and GaN/AlGaN quantum well structures. The investigation is carried out by optical methods involving the observation of quenching of the exciton photoluminescence under an applied ...
A high power radiation source in the THz range with long pulse and narrow line width is required for diagnosing fusion type plasmas by collective Thomson scattering. Gyrotrons currently meet the requirements concerning power, pulse length and line width wh ...
Powerful THz radiation confined in one field period or less is an adequate tool for triggering nonlinear actions. We show results towards the realization of a tunable high-power THz source based on a laser-driven frequency conversion scheme in plasma and n ...