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Updated: Aug 14, 2026

Infrared Degenerate Four-wave Mixing with Upconversion Detection for Quantitative Gas Sensing
Published on: March 22, 2019
Distinction of gases with a semiconductor sensor depending on the scanning profile of a cyclic temperature
Satoshi Nakata1, Hirokazu Okunishi, Yusuke Nakashima
1Department of Chemistry, Nara University of Education, Takabatake-cho, Nara 630-8528, Japan. nakatas@nara-edu.ac.jp
Abstract:
A gas-sensing system based on a dynamic nonlinear response is reported to improve the selectivity in the sensor response toward sample gases. A cyclic temperature composed of fundamental and second harmonics was applied to a SnO(2) semiconductor gas sensor and the resulting conductance of the sensor was analyzed by fast Fourier transformation (FFT). The dynamic nonlinear responses to the gas species were further characterized depending on the scanning profile of the temperature. These characteristic sensor responses under the application of second-harmonic perturbation were theoretically considered based on a reaction-diffusion model for the semiconductor surface.
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