Multiple-frequency terahertz pulsed sensing of dielectric films

We report on a technique for the on-chip sensing of dielectric materials in the terahertz frequency range. We show that an array of band-stop filters, excited by integrated ultrafast photoconductive switches, can be used to sense dielectric loading at a number of distinct lithographically defined locations on a chip simultaneously, each location sensing a different terahertz frequency. This technique is expected to have a range of future applications in the field of on-chip terahertz systems, such as the analysis of deoxyribonucleic acid and other molecular films.