InGaAs-based bow-tie diode for spectroscopic terahertz imaging

Abstract

Suitability of InGaAs-based bow-tie diodes for a spectroscopic terahertz imaging is demonstrated by inspecting explosive simulators packed in a thick plastic container. The transmission images were obtained within the frequency range of 0.58-2.52 THz at room temperature using optimized bow-tie diode connection scheme. Content of sucrose and tartaric acid in the test samples was discriminated. Measured absorbance was found to be in a good correlation with Fourier spectroscopy data. Performance of room temperature THz imaging using the bow-tie diode was compared versus a commercial pyro-electric sensor.