Abstract

NASA’s Earth and space-science missions have motivated the investigation of methods to produce coherent radiation in the 1-3-THz spectral region, corresponding to 100-150-μm wavelengths, for use as local- oscillator sources in high-resolution-laser heterodyne spectrometers. Scientific applications of this technology include measurements of the hydroxyl radical (OH) at 2.5 THz in Earth's upper atmosphere, which is important because of its role in the destruction of ozone. In addition, astrophysicists are interested in the spectroscopy of the interstellar molecular cloud in this previously unexplored region of the electromagnetic spectrum. However, these measurements necessitate a space-based instrument because the lower atmosphere is largely opaque in this spectral region.

© 1995 Optical Society of America