A passively mode-locked soliton ring fiber laser is investigated that
utilizes a 4.5-cm erbium-ytterbium (Er-Yb) codoped waveguide amplifier
as the gain element. The resulting short cavity (1.3 m of fiber) elim
inates multipulsing behavior and reduces the effects of resonant sideb
ands, enabling generation of 116-fs solitons with a pulse energy of 16
0 pJ at a fundamental repetition rate of 130 MHz.