Multi‐wavelength Yb‐doped fiber‐ring laser

A multi‐wavelength ytterbium‐doped fiber‐ring laser is obtained using a spatial‐mode beating filter, placing a section of a G.652 fiber sample into the single Yb‐doped fiber ring cavity. Up to six stable laser wavelengths can be obtained in the region of 1030 nm at room temperature. By changing the states of the polarization controller, the amount of lasing wavelength and the space can be controlled.