The Q‐switching performance of BP/SnSe2 heterojunction saturable absorber in Er‐doped fiber laser.

In this paper, we report the first Q‐switching operation utilizing black phosphorus (BP)/SnSe2 heterojunction as the saturable absorber (SA) in an Er‐doped fiber laser. The BP/SnSe2 heterojunction was prepared by the liquid phase combination method and its properties were observed. Stable Q‐switching operations were achieved based on the BP/SnSe2 SA. The maximum peak power of 71.27 mW and the minimum pulse width of 910 ns were produced, respectively. This paper demonstrates the pulse modulation characteristics of BP/SnSe2 heterojunction SA in the midinfrared region for the first time, laying an important foundation for the application of heterojunction based on BP and two‐dimensional transition metal dichalcogenides. [ABSTRACT FROM AUTHOR]