arXiv subjects

Vyacheslav Mironov

Publications and source records attributed to Vyacheslav Mironov.

2 recordsLinked to original sources

arXiv2019

Optical excitation of surface plasmons and terahertz emission from metals

We propose a microscopic theory of terahertz (THz) radiation generation on metal gratings under the action of femtosecond laser pulses. In contrast to previous models, only low-frequency currents inside the metal are considered without involving electron emission. The presented model is based on plasmon-enhanced thermal effects and explains the resonant character of optical-to-THz conversion giving an adequate estimation for the full signal energy. Numerical modeling reproduces specific experimental features like delayed character of THz response and low conversion efficiency when the grating depth is too large.

physics.optics↗

arXiv2017

Terahertz emission from metal nanoparticles due to ultrafast heating

We demonstrate theoretically that ultrafast heating of metal nanoparticles by the laser pulse should lead to the generation of coherent terahertz (THz) radiation during the heat redistribution process. It is shown that after the femtosecond laser pulse action the time-dependent gradient of the electronic temperature induces low-frequency particle polarization with the characteristic timescale of about fractions of picosecond. In the case of the directed metallic pattern, the THz pulse waveform can be controlled by changing geometry of the individual particle. The generation mechanism proposed in this Letter can be used for interpretation of the recent experiments on the THz generation from metallic nanoparticles and nanostructures.

physics.optics↗