Abstract

The combination of periodically poled lithium niobate (PPLN) and diode-pumped, high-power fibre lasers allows the development of a wide range of compact, versatile, all-solid state parametric devices. For example, we have recently demonstrated a Q-switched erbium fibre laser pumped, widely-tuneable (1-5μm) nanosecond optical parametric oscillator (OPO) with a 10μJ threshold. A femtosecond optical parametric generator OPG has also been demonstrated using a frequency doubled, erbium fibre amplifier based Chirped Pulse Amplification (CPA) system pump source [1]. Thresholds as low as ~50nJ were demonstrated (600fs pulses at 780nm). In order to obtain such pulse energies these authors needed to employ a bulk diffraction grating pair as the pulse re-compressor within the CPA system. Use of a conventional fibre grating pulse recompressor was not possible due to the onset of non linearities within such structures at the powers levels required. Bulk grating compressors makes the system both complex and bulky and therefore far less attractive from a practical perspective. In this paper we report the development of a compact, picosecond OPG pumped by truly all-fibre CPA system.

© 1998 IEEE