S.M. Eaton, Istituto di Fotonica e Nanotecnologie (IFN)-CNR, Italy
G. Cerullo, Politecnico di Milano, Italy
R. Osellame, Istituto di Fotonica e Nanotecnologie (IFN)-CNR, Italy
Femtosecond laser microprocessing is a direct, maskless technique capable of inducing a permanent refractive index increase buried beneath the surface of transparent glasses and polymers, enabling photonic circuit fabrication in 3D geometries. We describe how the repetition rate influences the heat accumulation between laser pulses, which determines the regime of modification and the resulting morphological change in glasses in polymers. In most silicate and ...