Monolithic photonic crystal-based fiber-tip Fabry-Pérot static pressure sensor

We developed a monolithic photonic crystal-based optical fiber-tip static pressure sensor. The single-crystalline silicon, from which the sensor was built, ensures a low-stress membrane free of the buckling that is characteristic of oxide membranes on silicon. The photonic crystals on the membrane improve its reflectance and sharpen the Fabry-Pérot resonance peaks. The sensor head fits within an 11 mm × 1.8 mm × 1.8 mm volume and exhibits a sensitivity of 6.76 nm/kPa with excellent linearity up to 3.73 kPa.