High-efficiency fiber-cladding power stripper based on all-dielectric optical thin films

Although conventional fiber -cladding power strippers (CPSs) based on the techniques of high -index adhesive or corrosive liquids onto fiber inner cladding have been well developed, they are still facing challenges in special applications such as spaceborne or radiation -environment fiber lasers and amplifiers. In this paper, we propose and fabricate high -efficiency CPSs based on all -dielectric optical thin films. By numerically analyzing the propagation characteristics of cladding light at the thin film interface, we design a high -index Ta2O5 CPS and Al2O3 CPS with single- and cascaded -layer films coated onto the fiber inner cladding, respectively. In our experiment, the CPSs are successfully fabricated onto the inner -cladding surface of 10/125 double -clad fiber based on ion -beamassisted deposition technology. The stripping efficiency for the 976 nm residual cladding power was measured up to 99.38%, and the stripping power of the fiber CPS without active cooling can be 24 W at least. Such CPS could be advantageous for applications in spaceborne-based fiber lasers or amplifiers (e.g., gravitational wave detection, spaceborne lidar). (c) 2024 Optica Publishing Group