Continuously tunable coherent spectroscopy for the 0.1–1.0-THz region

Abstract

A spectroscopic system is described that provides coherent, continuously tunable coverage from below 100 GHz to above 1 THz. The phase of the microwave power is directly relatable to WWVB and the spectral purity is such that linewidths of less than 0.01 MHz (HWHM) can be observed without apparent broadening. The flexibility and general applicability of this system make possible a wide variety of submillimeter experiments. In order to illustrate the capabilities of this system we report observations of H2O and CO in the region between 300 and 1100 GHz.