Fig. 3: Numerical analysis of terahertz asynchronous twin-comb sensing applications.
From: Terahertz asynchronous twin-comb for prefiguring hypersensitivity beyond spectrum domain
a Sensing diagram. The white and red dashed areas represent the equivalent volume of the sensing region and sample. b Terahertz twin-comb sensitivity curves related to the sample spatial proportion. The color lines represent the sensitivity contours. ηl and ηd represent the normalized length and height proportion of the sample within the yz-plane of the sensing area in (a). The white rows are the gradient of sensitivity. c The twin-comb sensor time-frequency dependent sensitivity curves in different characteristic resonance frequency orders. Saturation represents sensitivity. Wider stripes represent higher-order characteristic resonance frequencies. d The twin-comb spectral response to the refractive index of the sample. Δn means the change in refractive index of the sample. e Contour of characteristic resonance frequency corresponding to different sample refractive index. The red-white-blue gradient contour means the transmission difference in the twin-comb dual-envelope. S indicates the sensing sensitivity. R2 represents the coefficient of determination.
