Abstract
Nonexponential decay of the 4 F 3/2 upper laser state in Nd:YLF was observed with time-resolved fluorescence spectroscopy and small-signal gain probes in low-doped (1.16-at. %) samples when intensely pumped to high population inversions. A rapid initial decay is observed after Q-switched laser pumping, followed by a longer nonexponential decay that is clearly identified as a phase of migration-assisted energy-transfer upconversion (ETU) in the hopping regime. During this phase, a rate-equation treatment is valid and the macroscopic ETU coefficient, α2 = (0.98 ± 0.03) × 10-16 cm3/s, is directly evaluated from the decay kinetics. The ETU and the migration microparameters are also estimated to be C da* ≈ 200 × 10-40 cm6/s and C dd ≈ 1000 × 10-40 cm6/s, respectively, and are compared with theoretical values found in the literature. On the basis of these values, rate-equation treatments of intensely pumped Nd:YLF are not strictly valid.
© 1999 Optical Society of America
Full Article | PDF ArticleMore Like This
V. Ostroumov, T. Jensen, J.-P. Meyn, G. Huber, and M. A. Noginov
J. Opt. Soc. Am. B 15(3) 1052-1060 (1998)
Ignacio Iparraguirre, Rolindes Balda, Mihail Voda, Mohamed Al-Saleh, and Joaquin Fernandez
J. Opt. Soc. Am. B 19(12) 2911-2920 (2002)
Carlos Jacinto, Samuel L. Oliveira, Tomaz Catunda, Acácio A. Andrade, John D. Myers, and Michael J. Myers
Opt. Express 13(6) 2040-2046 (2005)