Three-dimensional dielectric crystalline waveguide beam splitters in mid-infrared band by direct femtosecond laser writing

We report on the fabrication of three-dimensional waveguide beam splitters in a dielectric Bi4Ge3O12 (BGO) crystal by direct femtosecond laser writing. In the laser written tracks of BGO crystal, positive refractive index is induced, resulting in so-called Type I configuration waveguiding cores. The...

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Bibliographic Details
Authors: He, Ruiyun, Hernández-Palmero, Irene, Romero Vázquez, Carolina, Vázquez de Aldana, Javier R., Chen, Feng
Format: article
Status:Published version
Publication Date:2014
Country:España
Institution:Universidad de Salamanca (USAL)
Repository:GREDOS. Repositorio Institucional de la Universidad de Salamanca
OAI Identifier:oai:gredos.usal.es:10366/146044
Online Access:http://hdl.handle.net/10366/146044
Access Level:Open access
Keyword:Beam splitters
Femtosecond laser writing
Glass waveguides
Laser machining
Laser sources
Quantum cascade semiconductor lasers
Description
Summary:We report on the fabrication of three-dimensional waveguide beam splitters in a dielectric Bi4Ge3O12 (BGO) crystal by direct femtosecond laser writing. In the laser written tracks of BGO crystal, positive refractive index is induced, resulting in so-called Type I configuration waveguiding cores. The “multiscan” technique is utilized to shape cores with designed cross-sectional geometry in order to achieve guidance at mid-infrared wavelength of 4 μm. The fundamental mode guidance along both TE and TM polarizations has been obtained in the waveguide structures. With this feature, we implement beam splitters from 2D to 3D geometries, and realize 1 × 2, 1 × 3, and 1 × 4 power splitting at 4μm.