Project 1.2 Materials and Devices for Terahertz Generation and Detection

Overview

The bandwidth available from most commercial lasers today is around 3.5 THz because of limitations in the materials used for the emitter and detector (typically inorganic EO crystals such as ZnTe). By combining very short laser pulses with EO polymers, the entire 100-THz bandwidth, with no spectral gaps, can potentially be made available. This is of great interest from a security standpoint since accurate discrimination of chemical/biological agents and explosives requires spectroscopic capabilities in the 5-30 THz spectral range. Building on our successful demonstration of a wide bandwidth (> 12 THz) gapfree THz system based on EO polymers, CMDITR researchers are striving to utilize this advance to create a THz spectrometer that has an even wider bandwidth response (0-30 THz) and a brighter THz source. Successful implementation of such a system will require identification of materials with low absorption in that band, low group velocity dispersion (GVD), and very high EO coefficient (r33 preferably > 300 pm/V).