Passively Q-switched all-fiber lasers generating cylindrical vector beams with 2-dimensional material saturable absorbers

In this paper, we present systematic experimental demonstrations of Q-switched all-fiber lasers generating cylindrical vector beam (CVB) outputs with 2D-material-based saturable absorbers, including graphene and black phosphorus (BP). The graphene and BP saturable absorbers are both fabricated by an optically driven method. Both radially and azimuthally polarized CVB laser pulses are realized by adjusting a pair of polarization controllers combined with an offset splice spot and a few-mode fiber Bragg grating. Our experimental effort provides a concise, reliable, and complete all-fiber laser route towards pulsed CVB emissions based on 2D-material saturable absorbers.