In an optical switching matrix, a common waveguide and a plurality of individual waveguides are connected by a selector that connects the common waveguide to a selected individual waveguide. The individual waveguides are doped and light from a pump is injected into the common waveguide towards the selector. The selector selectively transmits this light to the selected individual waveguide. The resulting amplification in this waveguide reduces crosstalk. One application of these optical switching matrices is in fiber optic telecommunication networks.