Terahertz repetition frequencies from harmonic mode-locked monolithic compound-cavity laser diodes

Compound-cavity laser diodes are mode locked at a harmonic of the fundament al round-trip frequency to achieve repetition rates of up to 2.1 THz. The d evices are fabricated from GaAs/AlGaAs material at a wavelength of 860 nm a nd incorporate two gain sections with an etched slot reflector between them , and a saturable absorber section. Autocorrelation studies are used to inv estigate device behavior for different reflector types and reflectivity. Th ese lasers may find applications in terahertz imaging, medicine, ultrafast optical links, and atmospheric sensing. (C) 2001 American Institute of Phys ics.