Theory of the rooftop resonator: resonant frequencies and eigenpolarizations.

The eigenpolarizations and resonant frequencies are derived for a circular dielectric waveguide resonator (EH11 mode) terminated by perfectly reflecting metallic rooftop mirrors. It is demonstrated that, in the far-IR region, circularly polarized helical standing waves result from an arbitrary angular misalignment of the rooftop creases. Further, the right and left circularly polarized modes have different resonant frequencies.

Effects of passive isolation on several optically pumped far-infrared laser lines.

The effects of a recently introduced passive-isolation scheme for optically pumped far-infrared lasers have been investigated on several well-known far-infrared laser lines. In addition to increasing the laser output stability, the isolation scheme alters the pump-to-far-infrared power-conversion efficiency and the polarization state of the far-infrared output.

Compact, pulsed low-pressure far infrared laser for use in plasma diagnostics.

The operation of a pulsed, watt-level, low-pressure far infrared (FIR) laser is described. Single mode output powers of 0.1-1 W are obtained from several molecular gases in the 300-1200 microm region.