Fiber optic SPR sensing of liquids using copper and zinc oxide

Refractive index sensing of liquids by fiber optic SPR sensor using bi-layers of copper-zinc oxide has been experimentally demonstrated. Thicknesses of copper and zinc oxide layers are shown to affect the sensitivity of the sensor. Sensitivity is found to increase with increase in zinc oxide layer thickness till 15 nm and keeps reducing with additional augmentation in zinc oxide layer thickness beyond 15 nm. Optimized thickness of zinc oxide layer is ensured to be 15 nm. Sensor developed using 40 nm thick copper-15 nm thick zinc oxide bi-layers manifests good sensing action.