LAUSR

In this paper, we report an all-fiber actively mode-locked erbium-doped fiber laser based on the mode multiplexer/demultiplexer (MUX/DEMUX). Higher-order mode and mode-locked pulse outputs can be realized simultaneously. The mode-locking is achieved by using a LiNbO 3 Mach–Zehnder intensity modulator. Multiple linearly polarized (LP) modes in the ring fiber laser are generated by mode MUX/DEMUX. For different spatial modes (LP 01 , LP 11 , LP 21 , hybrid modes), 17.32 ns, 20.40 ns, 23.00 ns and 17.24 ns mode-locked pulse trains are successfully obtained, respectively. The output laser operates at the fundamental frequency of 8.064 MHz with center wavelengths of 1528.71 nm for LP 01 mode, 1528.30 nm for LP 11 mode, 1530.45 nm for LP 21 mode and 1530.05 nm for hybrid mode. Moreover, we also measure the slope efficiency, spectrum and intensity distribution. The results show that the proposed fiber laser has potential applications in mode-division-multiplexed systems, optical sensing and optical fiber communication.