title: Low-threshold self-starting femtosecond Ti:sapphire laser.
abstract: A low-threshold self-starting Kerr-lens mode-locked Ti:sapphire laser is demonstrated that uses a tight-focusing cavity design in conjunction with a semiconductor saturable-absorber mirror (SESAM). With 3% and 12% output couplers, we achieve mode-locking thresholds as low as 390 and 600 mW, respectively. Stable femtosecond laser pulses with average power of 114 mW are generated at a pump power of 1.2 W, which corresponds to a typical duration of 17 fs and bandwidth of 47 nm. Mode-locking operation is achieved in a pump power range of 600 mW to 4.8 W at an output coupling of 12%; the advantages of using a SESAM for low-power mode-locking operation are demonstrated.
authors.affiliation: Laboratory of Optical Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China.
authors.forename: Weijun
authors.initials: W
authors.lastname: Ling
authors.forename: Yulei
authors.initials: Y
authors.lastname: Jia
authors.forename: Jinghua
authors.initials: J
authors.lastname: Sun
authors.forename: Zhaohua
authors.initials: Z
authors.lastname: Wang
authors.forename: Zhiyi
authors.initials: Z
authors.lastname: Wei