Electronic tuning and phase-lock techniques for optically pumped far infrared lasers

A technique has been developed to phase-lock a tunable far-infrared laser to a reference laser at an offset frequency of the order of 500 kHz. The technique utilizes the Stark tuning method which compensates for fast frequency fluctuations and a piezoelectric tuner which corrects for changes in the laser cavity length. The technique has particular importance for infrared frequency synthesis, time generation from infrared frequency standards and directional and synthesized infrared communications. When the Stark technique is coupled to low-noise microwave sources and efficient multipliers, frequency synthesis will be possible over a broad region of the far-infrared wavelength region.