Composite laser fiber with Yb, Er co-doped phosphate glass core and silica cladding

Abstract

This letter is devoted to fabrication and tests of an optical fiber with a phosphate glass core in a silica cladding. The fiber preform was made by melting Yb, Er co-doped phosphate laser glass in a high-purity silica tube. 1.54 μm laser action was demonstrated under 1.06 μm pumping into the Yb absorption band.