title: Low-loss channel optical waveguide fabrication in Nd(3+)-doped silicate glasses by femtosecond laser direct writing.
abstract: Optical waveguides were fabricated in neodymium-doped silicate glass by using a low-repetition-rate (1 kHz) femtosecond laser inscription. Two different types of waveguide structure are fabricated. In the first, guiding occurs in the focal spot. In the second, guiding occurs in the region between the two filaments. The near-field intensity distribution, propagation loss, index profile reconstruction, and calculation of the modal intensity distribution by the beam propagation method of these waveguides are presented. On the basis of near-field intensity distribution of the light guided through the waveguides and the propagation loss measurement, the optimum writing conditions such as the pulse energy and scan velocity were determined. The waveguide written with 2.2 µJ pulse energy and 50 µm/s scan velocity shows strong guidance at 632.8 nm, with an index contrast of 7 × 10(-4) and a propagation loss of ~0.8 dB/cm.
authors: College of Physics and Engineering, Shandong Provincial Key Laboratory of Laser and Information Technology, Qufu Normal University, Qufu 273165, China. shilingli@sdu.edu.cn
authors: Shi-Ling
authors: SL
authors: Li
authors: Peigao
authors: P
authors: Han
authors: Meng
authors: M
authors: Shi
authors: Yicun
authors: Y
authors: Yao
authors: Bing
authors: B
authors: Hu
authors: Mingwei
authors: M
authors: Wang
authors: Xiaonong
authors: X
authors: Zhu
mesh_terms: D004867:Equipment Design; D019544:Equipment Failure Analysis; D005898:Glass / Q000737:chemistry / Q000528:radiation effects; D008027:Light; D009354:Neodymium / Q000737:chemistry* / Q000528:radiation effects*; D017640:Silicates / Q000737:chemistry* / Q000528:radiation effects*; D020349:Surface Plasmon Resonance / Q000295:instrumentation*
chemical_list: D017640:Silicates; D009354:Neodymium