Progress in color center lasers

We report here on two areas of color center laser (CCL) development. The first involves an optimization of the commercial room temperature (RT) operable CCL, "MALSAN", in which the active medium provides high generation efficiencies up to 40% for LiF:F/sub 2//sup -/ (1.08-1.27 /spl mu/m) and 25% for LiF:(F/sub 2//spl rArr/F/sub 2//sup +/) (0.82-1.1 /spl mu/m), and line widths less than 0.3 cm/sup -1/. The second area is a demonstration of two unique CCL optical configurations. One entails lasing across the entire emission region of the active medium (1.1-1.24 /spl mu/m for the F/sub 2//sup -/ CC and 0.85-1.09 /spl mu/m for the F/sub 2//sup +/ CC with efficiencies of 15% and 10%, respectively), with simultaneous frequency doubling in the blue-red spectral region (0.43-0.62 /spl mu/m). The other involves multifrequency lasing, using a special mask or image controller placed in the pump beam.<
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