Multicore Optical Fibres for an External Talbot Cavity

In the paper the application of multicore optical fibres in phased-locked high power lasers is presented. The manufacturing and properties of multicore active optical fibres were presented. The thermally stable aluminosilicate glass doped with $Nd^{3+}$ (0.5 mol%) ions were melted and used as cores in manufactured multicore optical fibres. Two configurations of double clad multicore optical fibres with the circular array containing 15 and 30 $Nd^{3+}$ doped cores on ring inside a large pump clad were realized. Absorption and luminescence spectra of obtained glasses and fibres were presented. An external plane mirror located at certain distance of the array forms the basic Talbot cavity. The possibilities of mode selection and phase-locking by using Talbot resonator applied to fabricated multicore fibres were investigated.