Optofluidic vapor sensing with free-space coupled 2D photonic crystal slabs
Abstract
We report here a compact vapor sensor based on polymer coated two-dimensional (2D) defect-free photonic crystal slabs (PCS). The sensing mechanism is based on the resonance spectral shift associated with the Fano resonance mode in the PCS due to the vapor molecule adsorption and desorption induced changes in both polymer thickness and polymer refractive index (RI). Sensitivity due to RI and thickness change were theoretically investigated respectively. With three different thicknesses of OV-101 polymer coating, sensitivity and response time were experimentally evaluated for hexane and ethanol vapors. The polymer demonstrated roughly four times higher sensitivity towards the hexane vapor than ethanol vapor. The PCS sensor with thicker polymer coating showed higher sensitivity to both hexane and ethanol vapors but exhibiting longer response time.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Mar 12, 2019
- Source ID
- 10.1038/s41598-019-41048-w
Entities
People
- Prithviraj Palit
- Priyanka Biswas
- Shuling Wang
- Weidong Zhou
- Yonghao Liu
- Yuze Sun
Organizations
- Army Research Office
- Cancer Prevention and Research Institute of Texas
- Division of Electrical, Communications & Cyber Systems