Abstract: In this work, we present the first proof of Ge 1-x Si x -on-Al 2 O 3 -based novel rib optical waveguide (WG) for N 2 O and CO gas detection at 4.5 and 4.67 μm, respectively. We optimize the rib WG structure using theoretical models to achieve high sensitivity, minimal detectable gas concentration, and low propagation loss. In terms of the device’s sensitivity and minimal detectable concentration of N 2 O and CO at λ = 4.5 μm and 4.67 μm, respectively, are excellent. The sensitivity and minimal detectable value ( Cmin ) for N2O (CO) for the optimized device structure are 1.75 x 10 -5 ppm-1 (6.8 x 10 -6 ppm -1 ) and 18.93 ppm (14.97 ppm), respectively. The C min value demonstrates a significant improvement compared to previously reported findings and international standards. These findings demonstrate that Ge 1-x Si x platforms pave the way for the development of high-performance, compact optical WGs for MIR applications.
DOI: 10.1109/LSENS.2024.3374360
Manuscript link: https://ieeexplore.ieee.org/document/10462156
Publisher: IEEE
Date of Publication: 07 March, 2024
Authors: HARSHVARDHAN KUMAR, APOORV SHARMA, and TANISHA BOHRA