An Erbium-Ytterbium Co-Doped Few-Mode Fiber Amplifier

Abstract

The invention discloses an erbium-ytterbium co-doped few-mode fiber amplifier, which sequentially comprises a light source laser, a first mode multiplexer, a pump beam combining unit, an erbium-ytterbium co-doped fiber, a cladding optical stripper and a The second mode multiplexer; the erbium-ytterbium co-doped fiber sequentially includes a core, an inner cladding and an outer cladding from the inside to the outside, and the core is co-doped with erbium ions and ytterbium ions. The refractive index of the core gradually increases from the inside to the outside, and the refractive index of the core and the outer cladding is smaller than that of the inner cladding. On the one hand, the invention improves the gain of the few-mode amplifier by co-doping erbium and ytterbium; on the other hand, the specific distribution of the refractive index of the optical fiber section increases the area of ​​the mode spot and reduces the power filling factor in the mode group. Under the layer pump structure, the differential modal gain between modes is significantly reduced, and the pump conversion efficiency is improved.

Description

technical field

[0001] The invention relates to the field of photoelectric communication, in particular to an erbium-ytterbium co-doped few-mode fiber amplifier. Background technique

[0002] At present, with the rapid development of optical communication spectrum utilization technology and digital signal processing technology, the data capacity that ordinary single-mode fiber can carry has reached the nonlinear Shannon limit (100 Tbit / s), which cannot meet the growing demand for network traffic. Spatial division multiplexing technology can improve channel capacity and transmission reliability by constructing multiple-input multiple-output (MIMO) spatial channels, and was first used in wireless communications where frequency band resources are scarce. In optical fiber communication, space division multiplexing technology uses a single core in a multi-core fiber, a few-mode fiber or an orthogonal mode in a multi-mode fiber as a transmission channel, and has achieved Pbit tran...

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