Femtosecond laser fabrication of tubular waveguides in poly(methyl methacrylate).

School of Optics and Center for Research and Education in Optics and Lasers, University of Central Florida, Orlando, Florida 32816, USA.
Optics Letters (Impact Factor: 3.39). 09/2004; 29(16):1840-2. DOI: 10.1364/OL.29.001840
Source: PubMed

ABSTRACT Femtosecond laser direct writing is employed for the fabrication of buried tubular waveguides in bulk poly(methyl methacrylate). A novel technique using selective chemical etching is presented to resolve the two-dimensional refractive-index profile of the fabrication structures. End-to-end coupling in the waveguides reveals a near-field intensity distribution that results from the superimposition of several propagating modes with different azimuthal symmetries. Mode analysis of the tubular waveguides is performed using the finite-difference method, and the possible propagating mode profiles are compared with the experimental data.

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