Supercontinuum generation in orientation-patterned gallium phosphide

Supercontinuum generation in bulk media is not normally observed at the nJ-level pulse energies available from high-repetition-rate femtosecond oscillators. Here, we present results demonstrating how a visible supercontinuum can be produced in bulk orientation-patterned gallium phosphide from 100-MHz 1040-nm femtosecond pulses with energies of up to 32 nJ. High-order parametric gain near 550 nm, seeded by self-phase-modulated spectral sidebands, underpins this new and simple supercontinuum process which yields an output spectrum spanning from the blue/green to the red.