Femtosecond-laser-encoded distributed-feedback color center laser in lithium fluoride single crystals

金沢大学教育学部A distributed-feedback (DFB) color-center laser was fabricated by the holographic encoding method using an infrared femtosecond (fs) laser. Laser active color centers, waveguide structures and permanent gratings were written deep in lithium fluoride (LiF) crystals. It was shown that a refractive index change estimated from a guide propagation method was approximately +1% at a wavelength of 633 nm. The results show that the fabricated DFB laser structure oscillates at room temperature