Chirped-frequency generation in a translated-grating-type frequency-shifted feedback laser.

The properties of a frequency-shifted feedback (FSF) laser using a translated grating as the frequency-shifting element are investigated. FSF operation is attained by feedback of the first-order diffracted light from a grating coupler, which is translated in a direction perpendicular to the grating normal. A diode-pumped Nd:YVO(4) gain medium is used. Chirped-frequency components are periodically generated with a chirp rate of 1.8 THz / s. The unique spectral characteristics of this device are demonstrated with a Michelson interferometer and a heterodyne experiment.