Multi-wavelength Operation of an Er³⁺-doped Fiber Laser at Room Temperature with a Novel Optical Fiber Mach-Zehnder Interferometer

A novel multi-wavelength erbium-doped fiber laser with a double-pass Mach-Zehnder fiber interferometer acting both as a comb filter and as a reflection mirror is demonstrated. The spatial hole burning effect introduced by the standing wave cavity configuration enables the simultaneous operation of multiple wavelengths in the homogeneously broadened erbium-doped fiber at room temperature. In the experiment,simultaneous oscillation of four wavelengths at room temperature has been obtained.