A Compact 500 MHz Femtosecond All-Fiber Ring Laser

Abstract

We demonstrate a fundamentally mode-locked all-fiber ring laser with the repetition rate up to 500 MHz and pulse duration of 250 fs at 1.5 µm. Only an optical integrated module, a 4.8 cm Er3+/Yb3+-codoped phosphate glass fiber, and a polarization controller are employed to construct the all-fiber ring cavity. Stable mode-locking laser is output by adjusting the polarization controller.

Facile Synthesis of Monodispersed Titanium Nitride Quantum Dots for Harmonic Mode-Locking Generation in an Ultrafast Fiber Laser

“…At present, there are mainly two methods in fiber lasers to achieve high-repetition-rate pulses, one is to shorten the cavity length of the fiber laser resonator, and the other is passively harmonic mode-locked technology [7]. Because the repetition rate of a fiber laser is inversely proportional to the cavity length, if the repetition rate reaches the order of 100 MHz, the cavity length based on shortening the cavity length must be limited to less than two meters [8,9]. Each component has its own physical size, and the length of the gain fiber will be limited, resulting in insufficient optical gain.…”

Femtosecond laser based on a multicomponent fiber with a 3 wt.% Er-doped phosphate core and silica cladding

“…The NPE technique always shows fast-saturable losses independent of the operation wavelength [9] and thus it provides pulse duration in the subpicosecond range. This technique, together with heavily codoped Er/Yb phosphate fibers, allowed for getting repetition rates up to 500 MHz [10].…”

783 MHz fundamental repetition rate all-fiber ring laser mode-locked by carbon nanotubes

“…[16][17][18][19] Compared to Yb-doped silica fibers, Er-doped silica fibers have lower gain efficiency, therefore, many of the reported high repetition rate fiber lasers in 1.5 μm band are based on highly Er-doped or Er/ Yb co-doped phosphate glass fibers. [20][21][22] In 2016, J. Zhang et al demonstrated a 517 MHz ring fiber laser mode-locked by nonlinear polarization evolution (NPE) using commercialized highly Er-doped silica fiber. 23) In 2023, using the same oscillator design, the cavity length was further decreased to 22.5 cm, corresponding to a repetition rate of 895 MHz.…”