Small-signal gain measurement in a Ti:Al/sub 2/O/sub 3/ amplifier

A small-signal single-pass power gain of e/sup 5.2/=180 has been measured for a signal in the pi polarization at 790.7 nm in a longitudinally pumped Ti:Al/sub 2/O/sub 3/ amplifier. A double-pass power gain of e/sup 5.2/ approximately=10/sup 4/ has been attained for the same polarization at 799.8 nm. The ratio of the gain cross sections at 632.8 and 790.7 nm is 1/25. The gain anisotropy at 632.8 nm is g/sub pi //g/sub sigma /=2.3. The lifetime of the upper lasing level decreases with increased pumping, probably as the result of amplified spontaneous emission.<
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