Lin Han

High-power 880-nm diode-directly-pumped passively mode-locked Nd:YVO 4 laser at 1342 nm with a semiconductor saturable absorber mirror

A high-power 880-nm diode-directly-pumped passively mode-locked 1342 nm Nd:YVO₄ laser was demonstrated with a semiconductor saturable absorber mirror (SESAM). The laser mode radii in the laser crystal and on the SESAM were optimized carefully using the ABCD matrix formalism. An average output power of 2.3 W was obtained with a repetition rate of 76 MHz and a pulse width of 29.2 ps under an absorbed pump power of 12.1 W, corresponding to an optical-optical efficiency of 19.0% and a slope efficiency of 23.9%, respectively.

High-power diode-directly-pumped tenth-order harmonic mode-locked TEM00 Nd:YVO4 laser with 1 GHz repetition rate

A high-efficiency high-power diode-directly-pumped tenth-order harmonic mode-locked TEM00 Nd:YVO4 laser with 1 GHz repetition rate was first demonstrated. The maximum output power was 10.4 W with optical-optical efficiency of 41.8% and slope efficiency of 78.1%, respectively, the pulse width was about 30 ps at the output power of 9.6 W. Based on the large third-order nonlinearity of Nd:YVO4, the tenth-order harmonic mode-locked pulses were induced by the intensity-dependent Kerr effect and the cooperative action of counter-propagating pulses colliding in the laser crystal for a colliding-pulse-modelocking-like cavity. The pulses were further modulated by a semiconductor saturable absorber mirror.

Efficient optical image amplifier using periodically poled lithium niobate

An efficient optical image amplification scheme has been proposed and demonstrated using the quasi-phase-matched optical parametric amplifier. Pumped with the 152 μJ per pulse pump laser at 532 nm, the input weak infrared image at 1064 nm with 3.5 pJ energy is amplified with a 55 dB optical gain using only a 3 mm long MgO-doped periodically poled lithium niobate (MgO:PPLN) crystal. A spatial resolution of 17 lines/mm on the surface of the PPLN crystal is obtained. Further numerical simulation indicates that our scheme enables efficient image enhancement with a long pulsed pumping source, such as nanosecond lasers.

Passively mode-locked grown-together composite YVO4/Nd:YVO4 crystal laser with a semiconductor saturable absorber mirror under 880-nm direct pumping

A passively mode-locked grown-together composite YVO4/Nd:YVO4 crystal laser is demonstrated with a semiconductor saturable absorber mirror by 880-nm laser-diode direct pumping. Under the absorbed pump power of 24.9 W, a maximum output power of 10.5 W at the repetition rate of 77 MHz is obtained, corresponding to the optical-optical conversion efficiency of 42.1% and the slope efficiency of 53.4%. The pulse width measured is 33 ps at the output power of 10 W.

Diode-pumped laser and self-frequency-doubling properties of a Nd 3+ :Na 3 La 9 O 3 (BO 3 ) 8 crystal

We report efficient, diode-pumped, self-frequency doubling (SFD) in the newly developed laser crystal Nd3+:Na3La9O3(BO3)8 (Nd:NLBO). More than 730 mW of fundamental output power at 1072 nm was achieved with a slope efficiency of 16.2%. With incident pump power of 8 W, 29 mW of green cw laser emission at 536 nm was observed with proper phase matching. This initial performance and the good optical properties of the crystalline host are encouraging for the development of a high power diode-pumped SFD visible light laser source.

4.6-W compact and efficient NdAl3(BO3)(4) thin-disk laser

The capabilities of a compact and highly efficient NdAl3(BO3)4 (NAB) thin-disk laser are demonstrated. Under a pump power of 8.2 W, the NAB disk laser delivers an average output power of 4.6 W at 1 063 nm, with a slope efficiency of 64%. The difficulty and complexity of the thin-disk laser design are minimized by the high absorbance of the NAB crystal. To reduce the thermal effect, low repetition frequency pulsed 885 nm direct pumping is considered an efficient way to realize a compact and highly efficient NAB thin-disk laser.