Laser Written Photonic Waveguides
The wave guiding structures are created by femtosecond laser pulses, which are tightly focused inside the bulk material. Due to the nonlinear absorption processes these lead to a permanent refractive index modification after relaxation of the plasma in the focal point. Under suitable irradiation conditions, the refractive index change is positive, allowing direct fabrication of guiding structures.
Using the combination of beam shaping with femtosecond laser writing we demonstrated a novel method to create waveguide coupler [pdf1] and splitter devices [pdf2] in fused silica. The major advantage of the beam shaping method is the possibility to create complex devices in a single sweep by simultaneously writing two or more waveguides with changing separation.
The advantages of laser written photonic waveguides is the possibility to incorporate these into existing devices, especially microfluidic devices, for the creation of an integrated optical detection and measurement system.
- Matthias Pospiech, Moritz Emons, Benjamin Vaeckenstedt, Guido Palmer, and Uwe Morgner : Single-sweep laser writing of 3D-waveguide devices, Optics Express 18, Issue 7, pp. 6994-700 (2010)
- Matthias Pospiech, Moritz Emons, Andy Steinmann, Guido Palmer, Roberto Osellame, Nicola Bellini, Giulio Cerullo, and Uwe Morgner : Double waveguide couplers produced by simultaneous femtosecond writing, Opt. Express 17, 3555-3563 (2009)