Optical bifurcated fiber diode-pumping for two-wavelength laser operation with the Yb3+-doped GdAl3(BO3)4 birefringent crystal

Thanks to diode pumping through an optical bifurcated fiber, we take benefit of the birefringence of the Yb3+-doped GdAl3(BO3)4 crystal to get two-polarization and two-wavelength laser operation both in CW and in passive Q-switch regimes. Typical differential slopes are 54% and 30% respectively for the o- and e-waves. In the pulse regime the two o- and e-pulses are synchronous but not simultaneous. Free running laser emissions near 1040 and 1046 nm for the e- and o-waves respectively were obtained with 2.5 nm FWHM.