Second harmonic generation of violet light in femtosecond-laser-inscribed BiB3O6 cladding waveguides

Depressed cladding waveguide structures have been fabricated in BiB3O6 nonlinear crystal by using femtosecond (fs) laser inscription. The nonlinear properties of original BiB3O6 crystal have been well preserved within the waveguide volume. Under 800 nm continuous wave laser pumping, the guided-wave second harmonic generation of violet light at 400 nm has been realized, with a maximum power of ~1.05 mW and a conversion efficiency of ~0.98%/W