Neodymium-doped yttrium lithium fluoride

Neodymium-doped yttrium lithium fluoride (Nd:YLF) is a lasing medium for arc lamp-pumped and diode-pumped solid-state lasers. The YLF crystal (LiYF₄) is naturally birefringent, and commonly used laser transitions occur at 1047 nm and 1053 nm.^[1]

It is used in Q-switched systems in part due to its relatively long fluorescence lifetime. As with Nd:YAG lasers, harmonic generation is frequently employed with Q-switched Nd:YLF to produce shorter wavelengths. A common application of frequency-doubled Nd:YLF pulses is to pump ultrafast Ti:Sapphire chirped-pulse amplifiers.

Neodymium-doped YLF can provide higher pulse energies than Nd:YAG for repetition rates of a few kHz or less. Compared to Nd:YAG, the Nd:YLF crystal is very brittle and fractures easily. It is also slightly water-soluble — a YLF laser rod may very slowly dissolve in cooling water which surrounds it.[1]

^ Pollak, T.; Wing, W.; Grasso, R.; Chicklis, E.; Jenssen, H. (1982). "CW laser operation of Nd:YLF". IEEE Journal of Quantum Electronics. 18 (2). Institute of Electrical and Electronics Engineers (IEEE): 159–163. Bibcode:1982IJQE...18..159P. doi:10.1109/jqe.1982.1071512. ISSN 0018-9197.

[1] Pollak, T.; Wing, W.; Grasso, R.; Chicklis, E.; Jenssen, H. (1982). "CW laser operation of Nd:YLF". IEEE Journal of Quantum Electronics. 18 (2). Institute of Electrical and Electronics Engineers (IEEE): 159–163. Bibcode:1982IJQE...18..159P. doi:10.1109/jqe.1982.1071512. ISSN 0018-9197.

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