NKT Photonics has introduced a version of its Crystal Fibre series double clad fibre. The DC-135-15-PM-Yb fibre is made with Crystal Fibre airclad technology and features low photodarkening. The polarisation maintaining Ytterbium fibre is typically used in fibre amplifier configurations for pulsed laser amplification.
The DC-135-15-PM-Yb fibre features a 16 micron mode field diameter Ytterbium core, which has a polarisation extinction ratio greater than 18dB. The 135 micron pump core diameter accepts pump light at numerical aperture values up to 0.6 for pumping at 915 or 976nm. Pump absorption is 8dB/m for 976nm pumping.
The fibre is designed for OEM use for industrial customers manufacturing fibre amplifiers. A signal-feedthrough fused fibre combiner for reverse pumping of the DC-135-15-PM-Yb is in development, planned for release in the beginning of 2010. The combiner will have standard pump and signal fibre interfaces for easy mating with single emitter pumps and fibre pigtailed seed sources/output isolators.