1 Department of Micro- and Nanotechnology, Technical University of Denmark2 Optofluidics, Department of Micro- and Nanotechnology, Technical University of Denmark
The ability to perform laboratory operations in compact systems is not only advantageous for the development of diagnostics tools and their production, but also provides unique opportunities to explore the natural world on the micro- and nanoscale. To this end, we focus on two optical schemes: 1) polymer-based distributed feedback (DFB) dye lasers, and 2) plasmonic V-grooves. Regarding the first, DFB dye lasers are well suited to serve as compact, minimal analyte volume and highly sensitive refractive index sensors, where changes occurring in an analyte result in readily measurable shifts of the laser emission wavelength. We provide a framework for designing optimized DFB laser sensors comprising a thin TiO2 guiding layer. Regarding the second, plasmonic V-grooves offer a means to control the trade-off between e-field confinement and propagation length by varying the V-shape profile, opening new prospects for unobtrusive particle and single molecule manipulation. We demonstrate a broad capability to tailor the properties of the plasmonic modes by subtly tuning the underlying Silicon V-groove geometry using conventional SiO2 growth. The approaches of 1) and 2) are considered with respect to the advantages they bring to lab-on-a-chip systems.