title: Efficient refractive-index modification of fused silica by a resonance-photoionization-like process using F(2) and KrF excimer lasers.
abstract: Novel materials processing by a multiwavelength excitation process using F(2) and KrF excimer lasers for high-efficiency and high-speed refractive-index modification of fused silica is demonstrated. We find this process to be essentially superior to single-wavelength F(2) -laser processing: The multiwavelength excitation process achieves more than twice the diffraction efficiency of fused silica modified by a F(2) laser at the same total number of photons in each irradiated laser beam supplied to the fused-silica substrate. This superiority is attributed to a resonance-photoionization-like process based on excited-state absorption.
authors.forename: Kotaro
authors.initials: K
authors.lastname: Obata
authors.forename: Koji
authors.initials: K
authors.lastname: Sugioka
authors.forename: Toshimitsu
authors.initials: T
authors.lastname: Akane
authors.forename: Katsumi
authors.initials: K
authors.lastname: Midorikawa
authors.forename: Naoko
authors.initials: N
authors.lastname: Aoki
authors.forename: Koichi
authors.initials: K
authors.lastname: Toyoda