Cladding-pumped passively mode-locked femtosecond fiber lasers

Summary form only given. We demonstrate for the first time that high-power and high-repetition-rate femtosecond fiber lasers can be constructed that require only simple broad-area diode-array pump lasers. To allow pumping with diode arrays, the standard single-mode erbium fiber of conventional oscillator designs is replaced with double-clad erbium/ytterbium fiber. Reliable femtosecond pulse operation is ensured by exploiting nonlinear polarization evolution for steady-state pulse shaping in environmentally stable cavity. Furthermore the use of chirped Bragg gratings allows the extension of the operation range of these types of laser into the picosecond regime.