Threshold optimization of all-solid-state Cr:forsterite lasers

The pumping threshold of a Cr:forsterite laser is lowered by optimizing a double-pass pumping in a sufficiently short crystal. This solution for the first time allows nearly room-temperature Cr:forsterite cw operation with a threshold as low as 330-mW at 1064 nm and permits the laser to be pumped with a single transverse mode vanadate minilaser delivering only 900 mW.