title: Integration of femtosecond laser written optical waveguides in a lab-on-chip.
abstract: We use direct femtosecond laser writing to integrate optical waveguides into a commercial fused silica lab-on-chip (LOC). We fabricate high quality waveguides intersecting the microfluidic channels and use them to optically address with high spatial selectivity their content. Fluorescence from the photoexcited volume is efficiently collected at a 90 degrees angle by a high numerical aperture fiber, resulting in a compact and portable setup. Our approach is quite powerful because it allows the integration of photonic functionalities, by simple post-processing, into commercial LOCs, fabricated with standard techniques. By taking advantage of the unique three-dimensional capabilities of femtosecond laser writing, more complex functionalities, such as splitters or Mach-Zehnder interferometers, can be implemented.
authors.affiliation: Istituto di Fotonica e Nanotecnologie-CNR, Dipartimento di Fisica, Politecnico di Milano, Milano, Italy.
authors.forename: Rebeca Martinez
authors.initials: RM
authors.lastname: Vazquez
authors.forename: Roberto
authors.initials: R
authors.lastname: Osellame
authors.forename: Daniela
authors.initials: D
authors.lastname: Nolli
authors.forename: Chaitanya
authors.initials: C
authors.lastname: Dongre
authors.forename: Hans
authors.initials: H
authors.lastname: van den Vlekkert
authors.forename: Roberta
authors.initials: R
authors.lastname: Ramponi
authors.forename: Markus
authors.initials: M
authors.lastname: Pollnau
authors.forename: Giulio
authors.initials: G
authors.lastname: Cerullo
mesh_terms: D005453:Fluorescence; D007834:Lasers; D044085:Microfluidics / Q000295:instrumentation*