High-energy soliton pulse generation with a passively mode-locked Er/Yb-doped multifilament-core large-mode-area fiber laser

The generation of high-energy pulses from rare-earth-doped fiber lasers has been under intense investigation for the past few years. The pulse energy achievable in mode-locked fiber laser systems is limited by nonlinear effects occurring during propagation through the fiber, mainly Kerr-nonlinearity, avoid self-consistent pulse evolution inside a fiber laser resonator and hinder the pursuit of higher pulse energies from mode-locked fiber lasers. Hence, the employment of low-nonlinearity large-mode-area fibers (LMA) opens the possibility of energy scaling. This has been demonstrated recently by a femtosecond ytterbium-doped fiber laser operating in the anomalous net-cavity dispersion regime emitting a pulse energy as high as 16 nJ [1]. More recently, single-mode operation for high energy amplification in the 1.5 µm wavelength region has been demonstrated based on a multifilament core fiber combining large area and high doping concentration [2].