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An efficient soliton mode-locking femtosecond Yb3 + : Y2SiO5 (Yb:YSO) laser at 1059 nm assisted with semiconductor saturable absorber mirror has been successfully realized and demonstrated. Nearly Fourier transform-limited pulse duration as short as 236 fs has been achieved with a pulse repetition frequency of 79.6 MHz and an average output power of 903 mW, corresponding to maximum pulse energy of 11.34 nJ and pulse peak power of 48 kW, respectively. The dependence of pulse duration on the intracavity pulse energy in soliton mode-locking regime has been further investigated and discussed, which is fitted by the soliton mode-locking theory and indicates the nonlinear refractive index n2 of the Yb:YSO crystal to be around 2.1 to 4.8 × 10 − 16 cm2 / W.

A diode-pumped passively mode-locked YVO4/ Nd:YVO4 composite crystal green laser with a semiconductor saturable absorber mirror (SESAM) and a intracavity frequency-doubling KTP crystal was realized. The maximum average output power of 2.06 W at 532 nm with a repetition rate of 100 MHz was obtained at a pump power of 15 W, corresponding to optical slop efficiency 17.2%. The 532 nm mode-locked pulse width was estimated to be approximately 18-ps.

The 2D photonic crystal superprism structures with a triangle array of air holes were designed and fabricated on the polymer slab by soft lithography method. The profile of the molded structures with 450 nm in diameter and 900 nm in lattice constant was examined by SEM. By means of experiment and measurement, the beam propagation angle that can be changed from positive to negative was obtained, when the input incident angle varied from 15° to 11°. And the superprism effect at near-infrared wavelength 1550 nm was demonstrated effectively.

A diode-pumped continuous-wave mode-locked (CWML) femtosecond Yb+3:(Gd0.1Y0.9)2SiO5 (Yb:GYSO) laser at 1058.5 nm with a semiconductor saturable absorber mirror (SESAM) was successfully realized and demonstrated. Pulses with a duration of 186 fs were obtained at a pulse repetition rate of 80.1 MHz with a maximum average output power of 564 mW, corresponding to a maximum single pulse energy of 7.04 nJ and peak power of 37.9 kW. To the best of our knowledge, this is the highest peak power ever obtained from a mode-locked femtosecond Yb:GYSO laser.

A passively mode-locked all-solid-state YVO4/Nd:YVO4 composite crystal laser was realized with a low temperature (LT) In0.25Ga0.75As semiconductor saturable absorber mirror. The saturable absorber was used as nonlinear absorber and output coupler simultaneously. Both the Q-switch and continuous-wave mode locking operation were experimentally realized. At a pump power of 4 W, the Q-switched mode locking changed to continuous wave mode locking. An average output power of 4.1 W with 5 ps pulse width was achieved at the pump power of 12 W, corresponding to an optical-optical conversion efficiency of 34.2%.