Abstract

Femtosecond OPO’s operated in near-IR region with repetition rates up to 10 GHz will become more and more important to evaluate optical devices in ultrafast optical communication systems. Up to now, two papers about picosecond OPO’s with repetition rates higher than 1 GHz have been published. A. Robertson et al.¹ reported a 2.5-GHz repetition-rate OPO synchronously pumped by a 2.5-GHz repetition-rate mode-locked diode oscillator amplifier system. B. Ruffing et al.² demonstrated a 1.334-GHz harmonic repetition-rate OPO synchronously pumped by an 83.4-MHz repetition-rate mode- locked Nd:YVO₄ system. The repetition rates of the OPO’s described in these two papers were determined by the cavity length of the OPO’s. A 10-GHz repetition-rate OPO asks for a cavity length of only 30 mm for a ring cavity, therefore it is difficult to realize such a high repetition rate because of spacial limit. Here we report on a new way to construct an OPO with a harmonic repetition rate which is determined by the cavity length difference between the OPO and its pump laser.

© 2002 Optical Society of America