Tapered Multicore Fiber for High-Power Laser Amplifiers

• Published in: IEEE photonics journal Vol. 14; no. 1; pp. 1 - 6
• Main Authors: Andrianov, A. V., Skobelev, S. A., Balakin, A. A., Anashkina, E. A., Litvak, A. G.
• Format: Journal Article
• Language: English
• Published: Piscataway IEEE 01-02-2022; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Fiber lasers; fiber non-linear optics; High power lasers; laser beam combining; Laser beams; Laser modes; Laser theory; Multicore processing; Optical fiber amplifiers; Refractive index; Refractivity
• ISSN: 1943-0655; 1943-0655; 1943-0647
• DOI: 10.1109/JPHOT.2021.3135349

The problem of coherent amplification of the out-of-phase mode in tapered multicore fibers with cores arranged in a ring and in a square lattice is studied theoretically. The stability of out-of-phase field distributions with respect to both inhomogeneities of the refractive index and the initial wave field distribution is demonstrated in numerical modeling. Coherent combining of radiation into a single beam with good quality and efficiency of about 80% for ring cores arrangement and more than 90% for square cores arrangement is possible. Achievement of 55 MW of total power at the output of a fiber with <inline-formula><tex-math notation="LaTeX">11 \times 11</tex-math></inline-formula> cores is numerically demonstrated.