ULTRABROADBAND RING OSCILLATOR FOR SUB-10-FS PULSE GENERATION

A four-mirror ring cavity formed by chirped dielectric mirrors is prop osed for self-mode-locked solid-state lasers. It offers, for the first time to our knowledge, the potential for approaching the gain-bandwid th limit in Ti:sapphire and related broadband lasers. Using this conce pt, we produced nearly bandwidth-limited 7.5-fs pulses from a feedback -initiated, self-mode-locked Ti:sapphire ring oscillator. Our experime nts provide new insight into the physics and limitations of sub-10-fs oscillators. (C) 1996 Optical Society of America