Dual-wavelength mode-locked laser based on evanescent field interaction with max phase saturable absorber

Abstract

For the first time, we proposed a dual-wavelength laser generation with a titanium aluminum carbide (Ti3AlC2) as a saturable absorber in an erbium-doped fiber laser cavity. The saturable absorber device based on the MAX phase Ti3AlC2 deposited onto D-shaped fiber has successfully triggered a dual-wavelength laser centered at 1533 nm and 1557 nm. The elemental composition and vibrational modes of the saturable absorber were analyzed by using energy-dispersive x-ray spectroscopy and Raman spectroscopy for chemical analysis. We also captured a strong saturable absorption of 2% and a non-saturable absorption of 49.2% at the 1.55-µm, confirmed its ability to generate pulses in the near-infrared wavelength spectrum. The dual-wavelength laser owns a pulse width of 280 ns, a repetition rate of 1.887 MHz, and a signal-to-noise ratio of ~63 dB. By varying the laser diode pump from 62-90 mW, a stable dual-wavelength laser was generated with the highest single pulse energy of 2.33 nJ, which corresponded to the output power of 4.4 mW. This demonstration shows the potential of MAX phase Ti3AlC2 as a saturable absorber in an all fiber-based laser cavity.