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.     

Diode-Pumped Self-Starting Mode-Locked Nd：YVO4 Laser with Semiconductor Saturable Absorber Output Coupler

By using a semiconductor saturable-absorber output coupler as a mode-locking device, we experimentally realized the operation of a diode-pumped passively mode-locked Nd:YVO4 laser. Stable laser pulses with duration of 2.3ps were generated at the output power of about 1W. With increasing the pump power to 9 W, the maximum mode-locked power of 1.7 W was obtained, which corresponds to a slope conversion efficiency of 44 % and opticalto-optical conversion efficiency of 19%.     

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 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.     

Diode-Pumped Passive Q-Switched 946 nm Nd：YAG Laser with a GaAs Saturable Absorber

We report, for the first time to our knowledge, a diode-pumped passive Q-switched 946nm Nd：YAG laser by using a GaAs as saturable absorber. The maximum average output power is 1.24 W at an incident pump power of 15 W, corresponding to a slope efficiency of 10%. Laser pulses with pulse duration of 70ns and repetition rate of 330 kHz are generated.     

A Passively Mode－Locked Diode－End－Pumped Nd：YAG Laser with a Semiconductor Saturable Absorber Mirror Grown by Metal Organic Chemical Vapour Deposition

We report the experimentM results of a mode-locked diode-end-pumped Nd:YAG laser with a semiconductorsaturable absorber mirror (SESAM) from which we achieved a lOps pulse duration at 150MHz repetition rate.The SESAM was grown by metal organic chemical vapour deposition at low temperature. The recovery time wasmeasured to be 0.5 ps, indicating the potential pulse compression to sub-picoseconds.     

A Compact Diode-Pumped Injection Seeded Nd：YAG Laser with Resonance-Detection Technique

A diode pumped injection seeded single-longit udinal-mode （SLM） Nd： YA G laser is achieved by using the resonancedetection technique in Q-switching operation. The pulsed oscillator laser uses a folded cavity to achieve compact construction. This system operates at 100 Hz and provides over 20 m J/pulse of single-frequency 1064 nm output. The M2 values of horizontal and vertical axes are 1.58 and 1.41, respectively. The probability of putting out single-longitudinal-mode pulses is 100%. The 355 nm laser output produced by frequency tripling has a linewidth less than 200 MHz. The laser can run over eight hours continually without, mode hopping     

A Bragg-Mirror-Based Semiconductor Saturable Absorption Mirror at 800 nm with Low Temperature and Surface State Hybrid Absorber

We present a novel 800-nm Bragg-mirror-based semiconductor saturable absorption mirror with low temperature and surface state hybrid absorber, with which we can realize the passive soliton mode locking of a Ti:sapphire laser pumped by 532-nm green laser which produces pulses as short as 37 fs. The reflection bandwidth of the mirror is 3Ohm and the pulse frequency is 107MHz. The average output power is 1.1 W at the pump power of 7.6W.     

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.     

Passively Mode-Locked Quasi-Three-Level Nd:LuVO4Laser with Semiconductor Saturable Absorber Mirror

We demonstrate a passively a Z-folded resonator. Using device, we achieve stable cw average output power under cw mode-locked Nd：LuVO4 laser operating on the quasi-three-level at 916nm with a semiconductor saturable absorber mirror （SESAM） as the passive mode-locking mode locking with 6.7ps pulse duration at repetition rate of 133 MHz and 88mW the pump power of 17.1 W.     

Green Output of 1.5 W from a Diode-Pumped Intracavity Frequency-Doubled Self-Q-Switched and Mode-Locked Cr,Nd：YAG Laser

We report a diode-pumped intracavity frequency-doubled self-Q-switched and mode-locked Cr,Nd：YAG/KTP green laser with a Z-type cavity, which produces 1.5 W of average power at 532nm with incident pump power 14.2 W. The individual mode-locked green pulse duration is about 560ps with 149 MHz repetition rate. Almost 100% modulation depth of the mode-locked green pulses is achieved at an incident pump power of 4.13 W. The maximum energy of Q-switched green pulse is 19.8μJ. The experimental results of pulse duration and pulse energy of Q-switched green pulse agree well with the theoretical calculations.     

A Laser-Diode End-Pumped Nd:YVO4 Slab Laser at 1342nm

A laser-diode end-pumped Nd：YVO4 slab laser with a fiat-concave stable cavity at 1342nm is demonstrated. Under the pumping power of 92 W, a cw laser of output 17.8 W is obtained with the slope efficiency of 25.6%.     

Harmonic Mode-Locked Ytterbium-Doped Fibre Ring Laser

We demonstrate a harmonic mode-locked ytterbium-doped fibre ring laser, which consists of a polarization-sensitive isolator, two polarization controllers, two 976nm laser diodes as the pump source and a two-segment ytterbium-doped fibre. Utilizing an additive pulse mode-locked technique based on nonlinear polarization evolution, the ytterbium-doped fibre laser can operate in mode-locked state by adjusting the position of polarization controllers. The cavity fundamental repetition rate is 23.78 MHz. We also observe the second- and third-harmonic mode locking in the normal dispersion region, and their repetition rates are 47.66 MHz and 71.56 MHz, respectively. Over-driving of the saturable absorber in the harmonic mode-locking pulse is analysed and discussed in detail.     

A Compact All-Solid-State 630-ps 9.43-kHz High Power Nd：YAG/Nd：YVO4 Hybrid Laser System

We present a simple and compact design for an all-solid-state laser amplifier system which can output 9.43-kHz 630-ps, 3.5-W pulse trains under 20 W absorbed pumping power. The excellent matching between the repetition of its seed source and the fluorescence lifetime of the amplifying medium makes it quiet efficient for the four-pass amplifier to be pumped in cw mode without need of any synchronization device between the oscillator and the amplifier. The entire setup just covers an area of 55 × 25 cm^2. The output average power fluctuation is less than ±1.5% within 10min and 3% within 6h.     

13-W picosecond Nd:GdVO4 regenerative amplifier with 200-kHz repetition rate

We report a diode-pumped picosecond Nd:GdVO₄ regenerative amplifier system designed for micro-machining applications. Nd:GdVO₄ was chosen as gain material because it offers – in comparison to the commonly used Nd:YVO₄ – improved thermal properties and a larger gain bandwidth. At the maximum repetition rate of 200 kHz, the system generated 6.8-ps-long pulses with a pulse energy of 65 μJ, which corresponds to an average output power of 13 W. At 100 kHz, the pulse energy increased to 123 μJ, whereas the average power of 12.3 W remained almost identical. The broadening of the pulses due to gain narrowing was investigated in dependence on the number of cavity round trips and on the repetition rate. At 200 kHz, the injected 5.3-ps-long pulses broadened slightly to about 6.8 ps.     

Efficient Diode-Pumped Tm：YALO3 Laser with a Pump Recycling Scheme

By using a pump recycling configuration, the maximum power of 8.1 W in the wavelength range 1.935-1.938 μm is generated by a 5-ram long Tm：YAIOa （4 at.%） laser operating at 18℃ with a pump power of 24 W. The highest slope efficiency of 42% is attained, and the pump quantum efficiency is up to 100%. The Tm：YAlO3 laser is employed as a pumping source of singly-doped Ho（1%）：GdV04 laser operating at room temperature, in which continuous wave output power of greater than 0.2 W at 2.05/μm is achieved with a slope efficiency of 9%.     

Sixth Harmonic of A Nd：YVO4 Laser Generation In KBBF for ARPES

We report that a deep ultraviolet （DUV） laser from the sixth harmonic of a 1064nm laser has been firstly used as light source in an ultrahigh energy-resolution angle-resolved photoemission spectroscopy （ARPES）. The wavelength is 177.3nm obtained by using the second harmonic KBe2BO3F2 crystal with a frequency tripled 1064nm Nd：YVO4 laser. The large flux （10^14 - 10^15 photons/s） and narrow line width （0.26 meV） are suitable for the ultrahigh-energy resolution ARPES. The laser-ARPES can be a powerful tool to study the electronic structure at and near the Fermi level of the superconductor and correlated materials. The laser-ARPES has worked more than 500 h already.     

A Single-Longitudinal-Mode Dual-Wavelength cw Tm,Ho:GdVO4 Microchip Laser

A liquid nitrogen cooled dual-wavelength Tm,Ho：GdVO4 microchip laser is reported. The output dual wavelengths axe at 2038.9nm and 2050.1 nm. At each wavelength, the laser has a single longitudinal mode. The threshold power is nearly 20mW and the slope efficiency is 18.7%. The single longitudinal mode output power reaches 98mW, and the ratio of power is about 60% （2038.9nm） and 40% （2050.1 nm）.