What is Terahertz (THz)?
Terahertz radiation is part of the electromagnetic spectrum lying between microwaves and the far-IR. This region has frequencies ranging from 0.1 – 10 THz and wavelengths from 3 mm to 0.03 mm. This spectral region is often referred to as the “Terahertz gap” as these frequencies fall between electronic (measurement of field with antennas) and optical (measurement of power with optical detectors) means of generation. Historically, little study of the interactions between these wavelengths and matter has been undertaken. The reason for this was the difficulty in generating and detecting terahertz. Recent advances in combining optical and electronic methods have allowed for generation and detection of very high signal-to-noise ratio and high data acquisition rates of 0.1 – 3 THz frequencies. Consequently, a surge of interest in and study of the terahertz region is underway.