High gain optically pumped far infrared laser
A new optically pumped far infrared (FIR) laser with separate pump beam reflector and FIR output coupler is developed. The configuration of the new FIR laser greatly simplifies the tuning of the laser and enables the optimization of the pump beam absorption without affecting the laser alignment.
1. A FIR laser comprises
a vacuum chamber,
a beam pump source coupled to the chamber,
a rear mirror with an off center hole,
a waveguide, wherein the rear mirror and waveguide are housed in the chamber,
a pump beam reflector coupled to the chamber opposite the rear mirror, and
an output coupler positioned external to the chamber, wherein the distance between the rear mirror and output coupler define the cavity length of the FIR laser.
2. The FIR laser of claim 1 , further comprising a vacuum window coupled to the chamber adjacent the rear mirror.
3. The FIR laser of claim 1 , wherein a beam output from the pump source is split into two beams to pump two identical FIR lasers.
4. The FIR laser of claim 1 , wherein the pump beam reflector and the output coupler are separate components.
5. The FIR laser of claim 1 , wherein the pump beam reflector is configured as a dichroic mirror and positioned on an output end of the chamber separated from the output coupler.
6. The FIR laser of claim 1 , wherein the rear mirror and the pump beam reflector are mounted to the ends of first and second bellows on opposite ends of the chamber.
7. The FIR laser of claim 6 , wherein the bellows allow angle adjustments between the rear mirror and the pump beam reflector.
8. The FIR laser of claim 1 , wherein the output coupler is movable to enable the cavity length to be adjusted for resonance.
9. The FIR laser of claim 3 , wherein the output coupler is movable to enable the cavity length to be adjusted for controlling a beat frequency between the two FIR lasers.
10. The FIR laser of claim 1 , wherein the pump beam reflector is configured as a vacuum window on the output end of the chamber.
11. The FIR laser of claim 1 , wherein the output coupler comprises a parallel mesh Fabry-Pérot.