TECHNIQUE FOR LOCKING AN EXTERNAL CAVITY LARGE-AREA LASER DIODE TO A PASSIVE OPTICAL CAVITY

摘要

A large-area semiconductor laser diode in an extended laser cavity is locked by a passive optical coupling to a passive resonator for frequency and amplitude stable buildup of an intracavity field in the passive resonator. The large-area laser diode may be a broad-area diode, a phased array, or a tapered amplifier. The extended laser cavity may be a linear cavity, or a ring cavity in either a double-pass or a single-pass configuration. Spatial beam cleanup and passive locking are simultaneously achieved. The concentrated power in the passive resonator is useful for accomplishing second harmonic generation, frequency summing and the like at high levels of efficiency and at low noise levels resulting from the frequency and amplitude stability within the passive resonator.