Diode-Pumped Quasi-Three-Level Passively Q-Switched Nd：GGG Laser with a Codoped Nd,Cr：YAG Saturable Absorber

We demonstrate the first quasi-three-level passively Q-switched Nd：GGG laser at 937nm using a Nd, Cr：YAG crystal as the saturable absorber. The dependences of the average output power, the repetition rate and the pulse width on the incident pump power are obtained. A maximum average output power of 1.18 W with repetition rate of 35kHz and pulse width of 45ns is achieved at an incident pump power of 18.3 W. The corresponding optical-to-optical and slope efficiencies are 6% and 10%, respectively.     

Diode-pumped passively Q-switched and mode-locked Nd:YLF laser with Cr~(4+):YAG saturable absorber

A diode-pumped passively Q-switched Nd:YLF laser was demonstrated by using saturable absorber of Cr4 :YAG. At the incident power of 7.74 W, pure passively Q-switched laser with per pulse energy of 210μJ and pulse width of 19.6 ns at repetition rate of 1.78 kHz was obtained by using Cr4 :YAG with initial transmission of 80%. At the incident power of 8.70 W, a Q-switched mode-locking with average output power of 650 mW was achieved, the overall slop efficiency was 16%, corresponding to the initial transmission of 85% of Cr4 :YAG.     

MXene Ti_3C_2T_x saturable absorber for pulsed laser at 1.3 μm

The excellent optical properties of MXene provide new opportunities for short-pulse lasers. A diode-pumped passively Q-switched laser at 1.3 μm wavelength with MXene Ti_3C_2T_x as saturable absorber was achieved for the first time. The stable passively Q-switched laser has 454 ns pulse width and 162 kHz repetition rate at 4.5 W incident pumped power. The experimental results show that the MXene Ti_3C_2T_x saturable absorber can be used as an optical modulator to generate short pulse lasers in a solid-state laser field.     

Diode-pumped passively Q-switched and mode-locked Nd:YLF laser with Cr4+:YAG saturable absorber

A diode-pumped passively Q-switched Nd:YLF laser was demonstrated by using saturable absorber of Cr4+:YAG. At the incident power of 7.74 W, pure passively Q-switched laser with per pulse energy of 210 Μj and pulse width of 19.6 ns at repetition rate of 1.78 kHz was obtained by using Cr4+:YAG with initial transmission of 80%. At the incident power of 8.70 W, a Q-switched mode-locking with average output power of 650 Mw was achieved, the overall slop efficiency was 16%, corresponding to the initial transmission of 85% of Cr4+ :YAG.     

Q-switched mode-locked diode-pumped Nd:YVO_4 laser with a saturable Bragg reflector

We demonstrated a diode-pumped passively Q-switched mode-locked Nd:YVO4 laser by using a relaxed saturable Bragg reflector (SBR). Stable mode-locked pulse train with the repetition rate of -230 MHz was achieved and the pulse train was modulated by the Q-switched envelope with the repetition rate of -150 kHz. The maximum output of 4 W was obtained under the pump power of 13.5 W. The optical-to-optical efficiency was 30%. We also discussed the transition of each process having emerged.     

Compact and efficient diode-pumped passively Q-switched Nd:GdVO_4 laser at 1.06μm

Diode-pumped passively Q-switched Nd:GdVO4/Cr4+:YAG lasers with a simple flat-flat cavity were demonstrated. The maximum average output power at 1.06 μm was 1.25 W. The highest peak power and pulse energy were 7.56 kW and 75μJ, respectively, with the pulse repetition rate of 11.1 kHz and pulse width of 10 ns at the incident pump power of 8 W.     

High-Power Passively Q-Switched Nd:YAG Laser at 1112 nm with a Cr~(4+):YAG Saturable Absorber

A high-power passively Q-switched Nd:YAG laser operating at 1112 nm with Cr~(4+):YAG as a saturable absorber is demonstrated.Under 808 nm diode-direct pumping,the maximum average output power of 2.73 W is achieved at the pump power of 16.65 W,corresponding to an optical-to-optical conversion efficiency of 16.4%.At the same time,the pulse width,pulse repetition rate,single pulse energy and peak power are 27.2ns,9kHz,303.3μJ and11.2kW,respectively.As far as we know,the result gives the highest average output power at 1112 nm generated by an 808 nm diode-end-pumped Nd:YAG laser.     

Passively Q-switched green laser operation using CdTe/CdS quantum dots

The direct generation of passively Q-switched lasers at a green wavelength has rarely been investigated in the past. In this Letter, we demonstrate a passively Q-switched praseodymium-doped yttrium lithium fluoride green laser at 522 nm using CdTe/CdS quantum dots as a saturable absorber. A maximum average output power of 33.6 m W is achieved with the shortest pulse width of 840 ns. The corresponding pulse energy and peak power reached 0.18 μJ and 0.21 W, respectively. To the best of our knowledge, this is the first demonstration in regard to a quantum dots saturable absorber operating in the green spectral region.     

Passively Q-Switched Nd：KLuW Laser with Semiconductor Saturable Absorber

We demonstrate a passively Q-switched Nd：KLu W laser with a semiconductor sat urable absorber mirror （SESAM） at wavelength 1070 nm. At a pump power of 1.3 W, the pulse width is measured to be about 17ns with repetition rate of lOkHz and with the average output power of 260roW. To our knowledge, this is the first demonstration of Nd：KLuW used for passively Q-switched laser with an SESAM.     

ReSe_2 as a saturable absorber in a Tm-doped yttrium lithium fluoride(Tm:YLF) pulse laser

This study investigates the applicability of a few-layer structure ReSe2 as a saturable absorber(SA) for demonstrating a passively Q-switched pulse laser. The ReSe2 SA had a modulation depth of 6.86%. The Q-switched experiment was successful in delivering a maximum average output power of 180 mW at the wavelength of1906.5 nm. The optimal pulse train had a pulse width of 1.61 μs and a repetition rate of 28.78 kHz. The experiment results verify that the few-layer structure ReSe2 could behave as an excellent SA at all-solid-state lasers, increasing the selection of SAs at near 2 μm lasers.     

1.12-W Q-switched Yb:KGW laser based on transmission-type Bi2Se3 saturable absorber

We present a passively Q-switched Yb:KGW laser based on a transmission-type saturable absorber of topological insulator:Bi_2Se_3.The saturable absorber is prepared on a 0.17-mm glass substrate and can translate intra-cavity for best performance nearly without influence on the laser mode.At a maximum pump power of 13.7 W,the central wavelength,pulse duration,repetition rate,and pulse energy of Q-switched pulse are 1043 nm,1.5 μs,175.4 kHz,6.39 μJ,respectively.The maximum output power is 1.12 W.To our knowledge,this is the highest average output power from passively Qswitched lasers with topological insulator saturable absorbers.     

A Diode-Stack End-Pumped Electro-Optically Q-Switched Nd:YAG Slab Oscillator--Amplifier System

A laser diode-stack end-pumped electro-optically Q-switched Nd：YAG slab oscillator-amplifier system with neardiffraction-limited output is demonstrated by a stable-unstable hybrid resonator. The average power of 100 W at a repetition rate of lOkHz with a pulse width 14.7ns and average power of 76.3 W at a repetition rate of 5kHz with a pulse width of 10.2ns are measured. At the repetition rate of 10 kHz and at an output power of 89 W, the beam quality factors M^2 in the unstable and stable directions are 1.3 and 1.5, respectively.     

Diode-Pumped Passively Q-Switched Yb：YAG Microchip Laser with a GaAs as Saturable Absorber

A passively Q-switched Yb: YAG microchip laser has been constructed by using a doped GaAs as the saturable absorber as well as the output coupler. At 13.5 W of pump power the device produces high-quality 3.4μJ 52ns pulses at 1030nm with a pulse repetition rate of 7.8 kHz in a TEM00-mode.     

Q-Switched Large-Mode-Area Yb-Doped Fibre Laser Using GaAs as Saturable Absorber

A passive Q-switched large-mode-area Yb-doped fibre laser is demonstrated using a GaAs wafer as the saturable absorber. A high Yb doping concentration double-clad fibre with a core diameter of 30μm and a numerical aperture of 0.07 is used to increase the laser gain volume, permitting greater energy storage and higher output power than conventional fibres. The maximum average output power is 7.2W at 1080nm wavelength, with the shortest pulse duration of 580ns and the highest peak power of 161W when the laser is pumped with a 25W diode laser operating at 976nm. The repetition rate increases with the pump power linearly and the highest repetition rate of 77kHz is obtained in the experiment.     

High-power continuous-wave and high-energy Q-switched miniature Yb:Y_3Ga_5O_(12) crystal lasers

We report on the continuous-wave(CW) and passive Q-switching performance of a miniature Yb:Y_3Ga_5O_(12)crystal laser end pumped by a 935-nm diode laser. A maximum CW output power of 12.03 W is produced with an optical-to-optical efficiency of 54.4%, while the slope efficiency is 63%. In the passively Q-switched operation achieved with a Cr~(4+):YAG saturable absorber, an average output power of 2.12 W at 1025.2 nm is generated with a slope efficiency of 46% at a pulse repetition rate of 5.0 kHz. The pulse's energy, duration, and peak power are 424 μJ, 2.3 ns, and 184.3 k W, respectively.     

Passively Q-Switched Tm,Ho：YVO4 Laser with Cr：ZnS Saturable Absorber at 2 μm

A stable diode-pumped passively Q-switched Tm,Ho：YVO4 laser with Cr：ZnS saturable absorber is reported. The shortest pulse duration of -500 ns with the central wavelength of 2041 nm is obtained at the pump power of 7.4 W, corresponding to the pulse energy of 3.5 μd at repetition rate of 65 kHz.     

1514 nm eye-safe passively Q-switched self-optical parametric oscillator based on Nd~(3+)-doped MgO:PPLN

We examined a 1514 nm eye-safe passively Q-switched self-optical parametric oscillator. The nonlinear crystal is an a-cut Nd:MgO:PPLN crystal, and the size of the crystal was 6 mm × 2 mm × 30 mm with 0.4 at.%Nd~(3+) doped and a grating period of 29.8 μm. When the crystal absorbed 12.8 W, the output maximum singlepulse energy reached 39 μJ, and a pulse width of 6.1 ns at a repetition rate of 5.4 kHz was obtained.The peak power was 6 kW, giving a slope efficiency of 42%.     

Multi-watt Q-switched Nd:YVO_4 laser with GaAs output coupler

A passively Q-switched operation of a diode-pumped Nd.YVO_4 laser is demonstrated, in which a GaAsfilm is used as the saturable absorber as well as the output coupler. At the pump power of 10 W, a stablefundamental-mode average power output of 2.11 W was obtained with a pulse duration of 140 ns, pulseenergy of 76 μJ and pulse repetition rate of 28 kHz. A theoretical analysis that describes the passiveQ-switching dynamics of GaAs is presented.     

Passive Q-Switching of a Yb:LuVO_4 Laser with Cr~(4+):YAG:Approaching the Intrinsic Upper Limit of Repetition Rate

We demonstrate a diode pumped Yb:LuVO_4 laser that can be passively Q-switched by a Cr~(4+):YAG saturable absorber having an initial transmission as high as 99.3%.A maximum pulsed output power of 2.35 W is generated at a repetition rate of 285.7 kHz,approaching or very near the intrinsic upper limit imposed by the recovery time of the Cr~(4+):YAG saturable absorber,and the resulting pulse energy,duration and peak power are,respectively,8.2μJ,39.2ns and 0.209kW.     

A 52-mJ Ho：YAG Master Oscillator and Power Amplifier with Kilohertz Pulse Repetition Frequency

We report on a high energy, high repetition rate Ho：YAG master oscillator and power amplifier （MOPA）, res- onantly dual-end-pumped by Tm：YLF lasers at room temperature. At the pulse repetition frequency of i kHz, we demonstrate a maximum energy of 30mJ per pulse with a 28.2ns pulse width in a Ho：YAG oscillator system resonantly double-end-pumped by Tm：YLF lasers. A maximum energy of 52mJ per pulse with a 30.5ns pulse width is achieved in the Ho： YA G amplifier, corresponding to a peak power of approximately 1.7 MW. The output wavelength is at 2090.6nm and 2096.9nm, and a beam quality factor of M2-2.1 is achieved.