▎ 摘 要
We have experimentally demonstrated polarization-locked vector soliton generation in a passively mode-locked erbium-doped fiber laser by using a few-layer graphene deposited D-shaped fiber to act as a saturable absorber (SA). Due to the long light/graphene interaction length and the asymmetric structure, the SA used in this work has large polarization-dependent loss, and as a result, the stationary polarization-locked vector solitons can be generated, being different from the scalar solitons produced by the nonlinear polarization rotation technique. The formation mechanism of such solitons is studied and it is found that they are elliptically polarized solitons. (C) 2014 Optical Society of America