Far-infrared lasers pumped with tunable narrow band CO2-TEA lasers

Abstract

Progress in several important areas of far-infrared (FIR) laser research would be greatly facilitated by the availability of a tunable multi-atmosphere CO2-TEA laser with an oscillation bandwidth of ~ 100 MHz. The narrow bandwidth requirement is imposed by the dynamics of the FIR laser. Tunability is necessary because accidental coincidences between CO2 laser lines and absorption lines in FIR laser media are too rare to provide strong, efficient laser action across the full FIR spectrum. Tunable single longitudinal mode (SLM) pumping under appropriate conditions also shows promise of producing a broadly tunable Raman FIR laser. In this paper the pump laser spectral requirements are established by considering pertinent elements of FIR laser theory and the spectra of typical FIR laser molecules. Several techniques for tuning narrow-band CO2-TEA lasers are reviewed and their applicability to this problem is assessed.