Abstract

We have generated sub-single-cycle pulses of electromagnetic radiation with pulse energies of up to 0.8 µJ and pulse lengths shorter than 500 fsec.

The transmitter is a GaAs wafer illuminated at normal incidence by 120 fsec, 770 nm pulses from a Ti:Sapphire chirped-pulse amplifier system, while a pulsed electric field is applied across the surface. The generated pulses are used to study FIR radiation from an <111> InP wafer in an external bias field. The results can be explained by radiation from nonlinear polarizations.

Picosecond and sub-picosecond far-infrared (FIR) electromagnetic pulses have been generated using a number of optical switching techniques.[1-4] Most interesting for high power applications is the planar photoconductor which produces coherent FIR radiation in the directions of optical specular reflection and transmission when illuminated with ultrashort laser pulses.[4] Both GaAs and InP wafers have been used for this purpose.

© 1993 Optical Society of America