▎ 摘　　要

NOVELTY - The laser has a laser resonator cavity composed of a wavelength division multiplexer (2), an erbium-doped optical fiber (3), a polarization independent isolator (4), an output coupler (5), a graphene-lead sulfide quantum dot heterogeneous structure saturable absorber (6) and a single-mode optical fiber. An output end of a pump light source is connected with the 980 nm end of wavelength division multiplexer. A common end of the wavelength division multiplexer is connected with one end of the erbium-doped optical fiber. The other end of the graphene-lead sulfide quantum dot heterogeneous structure saturable absorber is connected with one end of the single-mode optical fiber. The other end of the single-mode optical fiber is connected with the 1550nm end of the wavelength division multiplexer to form an annular laser resonant cavity. USE - Mold-locking optical fiber laser with graphene-lead sulfide quantum dot heterostructure saturable absorber used in ultra-fast optical diagnosis, precise measurement, laser medical and laser nuclear fusion field. ADVANTAGE - The laser can generate stable pulse with signal-to-noise ratio up to 70 decibels, and has good application prospect. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a preparation method of graphene-lead sulfide quantum dot heterostructure saturable absorber. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of the optical fiber laser of the mold-locking optical fiber laser with graphene-lead sulfide quantum dot heterostructure saturable absorber. 2Wavelength division multiplexer 3Erbium-doped optical fiber 4Polarization independent isolator 5Output coupler 6Graphene-sulfide quantum dot heterostructure saturable absorber 7Single-mode optical fiber