Dual-wavelength interval tunable and multi-wavelength switchable high-performance fiber laser based on four-leaf clover suspended core fiber filter

•A tunable multi-wavelength fiber laser using four-leaf-clover fiber filter is proposed.•The filter is based on multimode interference, which is verified by simulation.•Switchable single- to six-wavelength laser with the OSNR above 50 dB are obtained.•Dual-wavelength lasers with the maximal tunable range of 41 nm is achieved.•The possible application in strain sensing and microwave communication are discussed.