Growth, spectroscopy, and laser characterization of Er:KGdYbY(WO) epitaxial layers.

We report on the composition of Er-doped KGdYbY(WO) layers to be grown onto undoped KY(WO) substrate providing fine lattice matching and high refractive index contrast with the substrate and fabrication of high optical quality Er(1.3  at. %):KGdYbY(WO) epitaxial layers with thickness up to 180 μm.

Graphene Q-switched Er,Yb:GdAl(BO) laser at 1550 nm.

A single-layer graphene saturable absorber is employed for passive Q-switching of an Er, Yb:GdAl(BO) (Er,Yb:GdAB) compact laser, representing the first Er-doped oxoborate laser Q-switched by graphene. This laser is based on a c-cut 1.8 at.