A novel four-air-hole multicore dual-mode large-mode-area fiber: Proposal and design

• A novel four-air-hole multicore dual-mode large-mode-area optical fiber is proposed.
• This fiber makes the second-order modes TE01 and TM01 cut-off, which can realize strictly dual-mode operation.
• The maximum effective area Aeff of fundamental modes is approximately 4025 μm2.
• The single-mode operation can be also realized by adjusting the structural parameters.

A novel four-air-hole multicore dual-mode large-mode-area optical fiber is proposed in this paper. The characteristics of the mode field distribution, the operating wavelength, the effective area Aeff and the bending loss of fundamental modes are calculated. The influence of the structural parameters on the operating wavelength, the effective index neff and the effective area of fundamental modes is also discussed. This fiber makes the second-order modes TE01 and TM01 cut-off while increasing the effective area of fundamental modes, which can realize strictly dual-mode operation. The maximum effective area of fundamental modes is approximately 4025 μm2. The single-mode operation can be also realized by adjusting the structural parameters. This fiber is simple to fabricate, and flexible to design. It can be used for large-mode-area high-power optical fiber laser and amplifier.