Preparation of large-mode-area optical fibers for high-power fiber lasers operating around 2 um

Sponsor: GAČR

Nr. 17-06479S

Principal Investigator: RNDr. Eva Mihóková,  Institute of Physics of the Czech Academy of Sciences

Co-principal Investigator: Ivan Kašík, Ph.D.

Members: Jan Mrázek, Ph.D.,

From: 2017-01-01

To: 2019-12-31

Fiber laser power has rapidly increased in last two decades. Large-mode-area fibers are a novel promising alternative to the conventional single- or multi- mode optical fibers which no longer meet the demanding requirement for use in high-power fiber lasers. The project is focused to the preparation and the characterization of active large-mode-area (LMA) optical fibers for high-power fiber-lasers operating at 2 um. Holmium-doped large-core preforms will be prepared by three independent approaches: 1) MCVD approach combined with solution-doping method, 2 ) Sol-gel approach, and 3) Repusil approach. Optimized large-core preforms will be drawn into LMA optical fibers with a core diameter larger than 50 um. Selected holmium-doped LMA fibers will be tested as an active medium in a fiber-laser set-up operating at 2 um. The characteristics of the laser will be evaluated. Achieved results will be compared and the advantages of individual approaches will be evaluated. The results will allow preparing novel high-power fiber
lasers operating around 2 um.