Silicon photonic wire biosensors: Sensing, instrumentation, and applications

Photonic wire evanescent field (PWEF) sensor chips have been developed for multiplexed label free molecular detection. The sensors are made using 260 nm $\times {\bf 450}$ nm cross-section silicon waveguides folded into spirals less than 200 $\mu {\bf m}$ in diameter, but with an overall sensor length of more than a millimeter. The long propagation length gives a response to molecular binding much better than currently available tools for …