Atomic xenon laser produces high output power
An RF-excited atomic xenon laser capable of providing a CW output of 5.5 W has been developed by a research group at Heriot-Watt University (Edinburgh, Scotland). The laser operates in the 2-4-µm region with efficiencies up to 0.8%. Atomic xenon lasers are of interest because their spectral region is useful but difficult to access with other lasers; potential applications include surgery and atmospheric remote sensing. DC-excited xenon lasers are, however, usually characterized as high-gain devices with low saturation, producing only milliwatt output. Although recent experiments with microwave and RF excitation have increased powers up to approximately1 W, the reason for the increase was unclear.
The xenon laser uses RF excitation at 49 MHz into a rectangular discharge slab made of metal and alumina. The length of the slab is 370 mm, the width ranges from 2 to 30 mm, and the thickness (interelectrode gap) ranges from 1 to 1.5 mm. Area scaling occurs as the width is changed, with a linear increase in power as the discharge slab area is increased. The output corresponds to 50 mW/cm2, and the highest power from the configuration is 5.5 W from the full width of 30 mm. The researchers believe that there is scope for making further improvements in the xenon laser.