Distributed‐feedback color center lasers in wide‐band gap materials fabricated by a pair of chirped femtosecond pulses

Abstract

A room-temperature-operated, pulsed distributed-feedback (DFB) LiF:F 2 color center laser was achieved. A distributed-feedback structure, based on non-erasable periodic gratings of laser-active color centers with fringe spacings as fine as ~510 nm, was fabricated by a pair of chirped near-IR femtosecond laser pulses. The DFB LiF:F 2 laser outputs at 710 nm were obtained with a linewidth of less than ~1 nm, the slope efficiency ~10 % and beam divergence ~20 mrad.