Thermal mechanism of laser-induced THz generation from metal particles

摘要

Ultrafast heating of metal nanoparticles by the laser pulse found to be the source of coherent terahertz (THz) radiation due to the heat redistribution processes. Numerical modeling showed 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.