PICOSECOND PHOTONICS

The basic principles of new ultrafast all-optical processing devices a re experimentally demonstrated One type of device relies on the intera ction between art input signal and two colliding spatial solitons of a different wavelength in a planar waveguide with third order nonlinear ity. The devices which belong to the second type are based on second o rder nonlinear interactions (degenerate difference frequency mixing) a nd operate as ultrafast sampling gate or as deflector or as phase conj ugator: We report in a second part the design and performances of a la ser that could be used to trigger the above mentionned systems. The la ser cavity has two arms and two separate diode-pumped laser crystals ( Nd/YAG). The two laser beams are coherently recombined inside the reso nator into a single Gaussian beam. Picosecond pulses emission is ensur ed by passive mode-locking thanks to a nonlinear mirror set-up.