Silicon photonic micro-ring resonators to sense strain and ultrasound

We demonstrated that photonic micro-ring resonators can be used in micro-machined ultrasound microphones. This might cause a breakthrough in array transducers for ultrasonography; first because optical multiplexing allows array interrogation via one optical fiber and second because the silicon-on-insulator technology allows cost-effective...

Demonstration of Large Coupling-Induced Phase Delay in Silicon Directional Cross-Couplers

We investigate directional couplers in silicon-on-insulator photonic technology. We theoretically and experimentally demonstrate a large coupling-induced phase delay that occurs when nearly all light is coupled from one waveguide to the other, i.e., when the coupler operates as a cross-coupler. We show that even a tiny asymmetry in the two...