Multifunctional all-fiber mode-locked laser based on graphene-integrated polarization-dependent microfiber resonator

•All-fiber laser based on graphene-integrated polarized microfiber knot resonator.•Soliton, harmonic, and dissipative four-wave-mixing mode-locking were achieved.•Q-switching pulsation was achieved.•The device acts as polarizer, comb filter, and nonlinear component simultaneously.•Saturable absorption, polarizing and four-wave-mixing are coupled in the device. A stable pulsed all-fiber laser based on the hybrid graphene microfiber knot resonator device is proposed and demonstrated. Unlike previous pulse generation mechanisms, the operation utilizes saturable absorption as well as the nonlinear-polarization-rotation effect introduced by the polarization-dependent feature of the device to enhance intracavity power for boosting multiple pulsation regimes. 15.5 MHz conventional soliton mode-locking pulse, 140 MHz 9-order-harmonic mode-locking pulse, 27.4 to 48.6 GHz high-repetition-rate dissipative four-wave-mixing pulse, and 50 kHz stable Q-switched pulse were achieved experimentally based on one device. The easily fabricated versatile device acts as a polarizer, comb filter, and nonlinear component simultaneously, thereby introducing a novel application of microfiber resonator devices in ultrafast and nonlinear photonics.