Broadband mm-wave sealed-volume liquid bio-sensor exploiting tailored delocalization of modal fields in a micro-scale silicon waveguide

We demonstrate mm-wave sensing of a sealed volume of bio-liquid via a dielectric waveguide’s evanescent fields, which are enhanced by narrowing the guide core in order to reduce field confinement. This is exploited to investigate whether a culture of Gliboblastoma cells effects a measurable change in the composition of a nutrient solution. A small discernible decrease in absorption is observed, indicating potential for future safe and noninvasive mm-wave diagnostic tools