Short-wavelength Yb:fiber laser analysis

Abstract

Yb:fiber lasers have shown excellent performance in the 980-1100 nm wavelength range. To extend the range below 980 nm, it becomes difficult to reach the transparent condition due to the smaller ratio between emission and absorption cross sections. As a result, a high demand of population inversion is needed, and the selection of pump wavelength as well as other intra-cavity parameters are crucial for lasing in the 920-960 nm wavelength range. To find a feasible solution, the pump wavelength, fiber length, and laser cavity transmittance were systematically studied. Based on the experimental result of a 960 nm Yb:fiber laser, the re-absorption loss and temperature dependent gain can be reliably modeled. The result shows promise in the development of a Yb:fiber laser at a wavelength as short as 920 nm.

Thin-disk Raman laser operation of Yb:YVO4/YVO4around 1120 nm

“…The Yb 3+ ion has two energy levels: 2 F 5/2 and 2 F 7/2 . The two energy levels will split into multi-energy levels and the energy level spacings are different in different crystal structures [6][7][8]. Generally, the ground state, 2 F 7/2 , is split into four subenergy levels of 2 F 7/2 (0, 1, 2, 3) and the excited state, 2 F 5/2 , is split into three sub-energy levels of 2 F 5/2 (0′, 1′, 2′).…”