Lithium neodymium tetraphosphate laser

Abstract
Laser action at λ=1.047 μm is reported in a lithium neodymium tetraphosphate crystal (LNP; LiNdP4O12) pumped longitudinally with a rhodamine 6G laser (λ=5965 Å) or a chopped Ar ion laser (λ=5145 Å). Comparing the measured threshold and round‐trip loss of the resonator of the LNP laser with that of the Nd:YAG laser, the effective emission cross section for the ion in the 4F3/2 manifold of LNP is found to be 1.65 times that of Nd:YAG.