Proceedings Article | 21 April 2017
Proc. SPIE. 10094, Frontiers in Ultrafast Optics: Biomedical, Scientific, and Industrial Applications XVII
KEYWORDS: Optical components, Femtosecond phenomena, Optical circuits, Silica, Waveguides, Solid state lasers, Nonlinear dynamics, Ytterbium, Objectives, Solid state physics
Laser direct writing of optical devices and circuits is attracted attention because of its ability of three-dimensional fabrication without any mask[1]. Recently, Yb-fiber or solid-state laser has been commonly used for fabrication in addition to traditional Ti:S laser. However, it is reported that waveguide cannot be fabricated in fused silica by using the fundamental light from Yb-based femtosecond laser[2]. Some groups reported on waveguide fabrication by using second-harmonic beam of such lasers[3], but wavelength conversion using nonlinear process has drawbacks such as destabilization of laser power and beam deformation by walk off. <p> </p>In this study, we investigated fabrication of low-loss waveguide in fused silica by using the fundamental beam (1030nm) from an Yb solid-state femtosecond laser with a pulse duration of 250 fs. The NA of focusing objective lens was 0.42. The fabricated waveguide was made to have a circular cross-section by shaping laser beam with a slit[4]. We fixed repetition rate to 150 kHz, and identified appropriate scan speed and pulse energy for fabrication of low loss waveguide. Waveguide fabricated with appropriate condition had a propagation loss of 0.2 dB/cm, and this is the first report on optical waveguides in a fused silica fabricated by femto-second laser pulses at a wavelength of 1030nm. <p> </p>[1]K. M. Davis, et. al., Opt. Lett 21, 1729(1996)<p> </p> [2]J. Canning, et. al., Opt. Mater. Express 1, 998(2011) <p> </p> [3]L. Shah, et. al., Opt. Express 13, 1999(2005) <p> </p>[4]M. Ams, et. al., Opt. Express 13, 5676(2005)
