Q-Switched and Noise-Like Mode Locked Er-Doped Fiber Laser Based on Nb2AlC Saturable Absorber

Abstract

Nb 2 AlC is a kind of ternary ceramic material whose special crystal structure makes it both the advantages of metal and ceramics. And it has good electrical conductivity and strong stability at room temperature. In this article, the saturable absorption of Nb 2 AlC based thin film have been investigated, showing that it has saturated light intensity of 0.21 MW/cm 2 and the modulation depth of 2.62%. Noise-like mode locked and Q-switched pulses output based on Nb 2 AlC thin film have been achieved in erbium-doped fiber laser cavity. The narrowest width of noise-like mode-locked pulses' envelope is 13 ns, the maximum single pulse energy is 1.5 nJ, and the full width at half-maximum (FWHM) of the narrowest coherent spike is 2.34 ps. The minimum pulse width of the Q-switched pulse is 8.6 μs and the maximum single pulse energy is 66 nJ. As far as we know, this is the first report of Nb 2 AlC's application in ultrafast optics.