Terahertz radiation generated by optical rectification at metal surfaces

This study presents an overview of THz time-domain experiments evidencing that the interaction of a high power femtosecond laser pulse with the metal surface leads to generation of a picosecond pulse with a broadband spectrum in the THz range. Thin gold films deposited onto dielectric substrates are used as samples. The generated electromagnetic field is studied in reflection geometry as a function of pump fluence, film thickness, incidence angle and polarisation.