Switchable generation of dual-wavelength homogeneous and heterogeneous pulse patterns in a double-cavity fiber laser

•A fiber laser with double gain cavities is originally built for constructing joint filtering functions.•Bidirectional switching between dual-wavelength homogeneous and heterogeneous pulse patterns can be experimentally realized by adjusting the polarization bias.•The switchable generation of dual-wavelength homogeneous and heterogeneous pulse patterns is proved by theoretical and experimental analyses to be due to the joint filtering functions induced by the two gain cavities of the fiber laser. We report the experimental generation of dual-wavelength homogeneous and heterogeneous pulse patterns in a double-cavity fiber laser. The double-cavity fiber laser is characterized by a 5-cm Fabry–Perót (F–P) gain minicavity incorporating into a 207-m ring cavity for constructing joint filtering effects to achieve dual-wavelength pulses. The homogeneous pattern is a superposition state of dual-wavelength discrete solitons, while the heterogeneous pattern is the coexistence of one noise-like pulse (NLP) and one soliton with wavelengths centered at 1559 nm and 1565.8 nm. Bidirectional switching between these two pulse patterns can be realized by adjusting the polarization bias. The switchable generation of dual-wavelength homogeneous and heterogeneous pulse patterns is proved by theoretical and experimental analyses to be due to joint filtering effects induced by the two gain cavities. Our work can provide a new method for achieving controllable complex pulse patterns.