Quantum Electronics

Nonlinear absorption in a Cr4+: Gd2SiO5crystal subjected to picosecond excitation

Konstantin V. Yumashev, Н. В. Кулешов, V. P. Mikhailov, V. G. Shcherbitskii, Pavel V. Prokoshin, S P Zhmako, B. I. Minkov

Published Jul 31, 1995• 4 citations

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Abstract

The optical absorption, temperature dependences of the luminescence intensity and decay time, and the transient absorption spectra of a Cr 4+ : Gd 2 SiO 5 crystal were determined by the picosecond excitation and probing method. An analysis of the results showed that the induced absorption observed in the 600–650 nm range was due to 3 T 2 ( 3 F ) → 3 T 1 ( 3 P ) transitions from the excited state. The lifetimes of the 3 T 2 ( 3 F ) and 3 T 1 ( 3 F ) levels were estimated to be 15 ns and 12 ps, respectively. The cross section for absorption from the first excited state at the wavelength of 616 nm was (1.1 ± 0.6)×10 -18 cm 2 and that for absorption from the ground state at λ = 540 nm was (2.2 ± 1.1)×10 -18 cm 2 .

DOI: 10.1070/qe1995v025n07abeh000431

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