Spectral analysis of 4F3/2 level in the Nd3+:YVO4 crystal

In order to study the spectroscopic characteristics of Nd³⁺:YVO₄ crystal, the absorption spectrum of the Nd³⁺:YVO₄ crystal was measured. The spontaneous emission rates, fluorescence branching ratios of the transitions from ⁴F_3/2 level as well as radiative lifetime of the ⁴F_3/2 level were calculated based on the Judd-Ofelt (J-O) theory. In addition, for the purpose of characterizing the emission properties of ⁴F_3/2 level in Nd³⁺:YVO₄ crystal, the fluorescence emission spectra were measured under the pumping of ∼808 nm laser. The emission cross section spectra of ⁴F_3/2 → ⁴I_9/2, ⁴F_3/2 → ⁴I_11/2 and ⁴F_3/2 → ⁴I_13/2 transitions were calculated by the Fuchtbauer-Ladenburg (F-L) theory. The peak emission cross sections of 0.9 μm (⁴F_3/2 → ⁴I_9/2), 1.06 μm (⁴F_3/2 → ⁴I_11/2) and 1.3 μm (⁴F_3/2 → ⁴I_13/2) were determined to be 0.32 × 10⁻¹⁹ cm², 13.1 × 10⁻¹⁹ cm² and 1.93 × 10⁻¹⁹ cm², respectively. The fluorescence lifetime of ⁴F_3/2 level was measured, and the quantum efficiency was calculated as well. In this work, the peak emission cross sections in ∼0.9 and 1.3 μm bands originated from ⁴F_3/2 level in Nd³⁺:YVO₄ crystal were determined based on the spectroscopic method for the first time, to the best of our knowledge.