Neodymium-doped graded-index single-crystal fibre lasers

The efficient technology is developed for growing high-quality doped single-crystal fibres by the mini-pedestal method with laser heating. The technology can be used to fabricate high-quality doped single-crystal fibres with a controllable radial gradient of the refractive index. The refractive-index profile in single-crystal fibres is studied experimentally. The efficient operation of a Nd³⁺ : YAG single-crystal fibre laser in the waveguide regime was demonstrated upon longitudinal pumping by a laser diode.