A compact, efficient and high-power laser diode （LD） single-end-pumped Nd：YVO4 laser with continuous-wave emission at 1342 nm is reported. With a single crystal single-end-pumped by fibre-coupled LD array, an outpu...A compact, efficient and high-power laser diode （LD） single-end-pumped Nd：YVO4 laser with continuous-wave emission at 1342 nm is reported. With a single crystal single-end-pumped by fibre-coupled LD array, an output power of 7.36W is obtained from the laser cavity of concave-convex shape, corresponding to an optical-to-optical efficiency of 32.8%. The laser is operated in TEM00 mode with small rms amplitude noise of 0.3%. The influences of the Nd concentration, transmissivity of the output mirror and the cavity length on the output power have been studied experimentally.展开更多
Diode pumped monolithic nonplanar ring laser has been developed, yielding single frequency laser and has the advantages of compactness, reliability and high efficiency. Its principles are given in detail and a monolit...Diode pumped monolithic nonplanar ring laser has been developed, yielding single frequency laser and has the advantages of compactness, reliability and high efficiency. Its principles are given in detail and a monolithic nonplanar ring laser is designed. As a result, a laser of hundreds milliwatts cw single frequency output was built up, placed in a magnetic field and pumped by LD. The optical conversion efficiency was more than 15% and the slope efficiency more than 30%. The laser beam had a good quality, with M 2 about 1 2.展开更多
We demonstrate an all-solid quasi-continuous-wave （QCW） narrow-band source tunable to sodium D2a line at 589.159 nm. The source is based on sum-frequency mixing between lasers at 1064 nm and 1319 nm in a LBO crystal...We demonstrate an all-solid quasi-continuous-wave （QCW） narrow-band source tunable to sodium D2a line at 589.159 nm. The source is based on sum-frequency mixing between lasers at 1064 nm and 1319 nm in a LBO crystal. The 1064 nm and 1319 nm lasers are produced from two diode side-pumped Nd：YAG master oscillator power amplifier （MOPA） laser systems, respectively. A 33 W output of 589 nm laser is obtained with beam quality factor M^2 = 1.25, frequency stability better than ±0.2 GHz and linewidth less than 0.44 GHz. A prototype 589 nm laser system is assembled, and a sodium laser guided star has been successfully observed in the field test.展开更多
A novel flat-flat resonator consisting of two crystals（Nd：YAG ＋ Nd：YVO4） is established for power scaling in a diode-end-pumped solid-state laser. We systematically compare laser characteristics between multi-seg...A novel flat-flat resonator consisting of two crystals（Nd：YAG ＋ Nd：YVO4） is established for power scaling in a diode-end-pumped solid-state laser. We systematically compare laser characteristics between multi-segmented（Nd：YAG ＋ Nd：YVO4） and conventional composite（Nd：YAG ＋ Nd：YAG） crystals to demonstrate the feasibility of spectral line matching for output power scale-up in end-pumped lasers. A maximum continuous-wave output power of 79.2 W is reported at 1064 nm, with Mx2= 4.82, My2= 5.48, and a pumping power of 136 W in the multi-segmented crystals（Nd：YAG ＋ Nd：YVO4）. Compared to conventional composite crystals（Nd：YAG ＋ Nd：YAG）, the optical-optical conversion efficiency of multi-segmented crystals（Nd：YAG ＋ Nd：YVO4） from 808 nm to 1064 nm is enhanced from 30% to 58.8%,while the laser output sensitivity as affected by the diode-laser temperature is reduced from 55% to 9%.展开更多
Generation of intracavity multi-wavelength and the basic principle of sum-frequency lasers are discused, and the current research status and development of laser diode pumped lasers are introduced in detail.
Development of high energy laser sources with nanosecond pulses at several hertz values for repetition rate has been very attractive in recent years due to their great potential for practical applications. With the re...Development of high energy laser sources with nanosecond pulses at several hertz values for repetition rate has been very attractive in recent years due to their great potential for practical applications. With the recent advancement in fabricating large size laser quality transparent ceramics, diode pumped solid-state laser generating pulse energy of 100 J at 10 Hz has been recently realized at HiLASE center using Yb:YAG ceramic with Cr:YAG cladding. This review discusses Yb based high energy lasers, specific laser geometries for efficient thermal management and the role of transparent ceramics in such diode pumped high-energy-class solid-state lasers around the world.展开更多
An efficient, stable diode-end-pumped simultaneous continuous-wave （CW） dual-wavelength laser operating at 1.319 and 1.338 ttm in a Nd：YAG crystal has been demonstrated. A total output power of 6.3 W is achieved at...An efficient, stable diode-end-pumped simultaneous continuous-wave （CW） dual-wavelength laser operating at 1.319 and 1.338 ttm in a Nd：YAG crystal has been demonstrated. A total output power of 6.3 W is achieved at an absorbed pump power of 15 W, with a slope efficiency of 43.5%. The instability of output power is less than 1%. With a type II critical phase-matched KTP crystal inserted into the cavity as frequency doubler, a maximum output power of 200 mW in red region is acquired. In addition, a sixwavelength laser operation at 1.319 μm, 1.338 μm, 1.356 μm, 659.5 nm, 669 nm, and 678 nm is observed.展开更多
A diode-pumped solid-state laser （DPSSL） with a high energetic stability and long service life is applied to ablate the steel samples instead of traditional Nd：YAG laser pumped by a xenon lamp, and several factors,...A diode-pumped solid-state laser （DPSSL） with a high energetic stability and long service life is applied to ablate the steel samples instead of traditional Nd：YAG laser pumped by a xenon lamp, and several factors, such as laser pulse energy, repetition rate and argon flow rate, that influence laser-induced breakdown spectroscopy （LIBS） analytical performance are investigated in detail. Under the optimal experiment conditions, the relative standard deviations for C, Si, Mn, Ni, Cr and Cu are 3.3%-8.9%, 0.9%-2.8%, 1.2%-4.1%, 1.7%-3.0%, 1.1%-3.4% and 2.5%-8.5%, respectively, with the corresponding relative errors of 1.1%-7.9%, 1.0%-6.3%, 0.4%-3.9%, 1.5%-6.3%, 1.2%-4.0% and 1.2%-6.4%. Compared with the results of the traditional spark discharge optical emission spectrometry technique, the analytical performance of LIBS is just a little inferior due to the less stable laser-induced plasma and smaller amount of ablated sample by the laser. However, the precision, detection limits and accuracy of LIBS obtained in our present work were sufficient to meet the requirements for process analysis. These technical performances of higher stability of output energy and longer service life for DPSSL, in comparison to the Q-switch laser pumped by xeon lamp, qualify it well for the real time online analysis for different industrial applications.展开更多
This paper demonstrates the passively mode-locked Nd：GdVO4 laser operating on the ^4F3/2-^4I9/2 transition at 912 nm by using a semiconductor saturable-absorber mirror for passive mode locking, stable continuous wave...This paper demonstrates the passively mode-locked Nd：GdVO4 laser operating on the ^4F3/2-^4I9/2 transition at 912 nm by using a semiconductor saturable-absorber mirror for passive mode locking, stable continuous wave modelocked 912nm laser was achieved with a repetition rate of 176 MHz. At the incident pump power of 17.7W, 22.6mW average output power of stable mode-locked laser was obtained with a slope efficiency of 0.3%.展开更多
This paper reports that the Tm^3＋：Lu2SiO5 （Tm：LSO） crystal is grown by Czochralski technique. The roomtemperature absorption spectra of Tm：LSO crystal are measured on a b-cut sample with 4 at.% thulium. Accordin...This paper reports that the Tm^3＋：Lu2SiO5 （Tm：LSO） crystal is grown by Czochralski technique. The roomtemperature absorption spectra of Tm：LSO crystal are measured on a b-cut sample with 4 at.% thulium. According to the obtained Judd-Ofelt intensity parameters Ω2=9.3155×10^-20 cm^2, Ω4=8.4103×10^-20 cm^2, Ω6=1.5908×10^-20 cm^2, the fluorescence lifetime is calculated to be 2.03 ms for ^3F4 → ^3H6 transition, and the integrated emission cross section is 5.81×10^-18 cm^2. Room-temperature laser action near 2μm under diode pumping is experimentally evaluated in Tm：LSO. An optical-optical conversion efficiency of 9.1% and a slope efficiency of 16.2% are obtained with continuouswave maximum output power of 0.67 W. The emission wavelengths of Tm：LSO laser are centred around 2.06μm with spectral bandwidth of -13.6 nm.展开更多
The Australian first working sodium guide star laser system has been designed and developed for various astronomical and space-related applications. A completely diode-pumped pulsed system was developed initially foll...The Australian first working sodium guide star laser system has been designed and developed for various astronomical and space-related applications. A completely diode-pumped pulsed system was developed initially followed by a largely fiber-based continuous wave (CW) system operating at 589 nm achieved through a unique wavelength conversion scheme by combining 1342 and 1050 nm through a sum frequency generation process. For the CW system, single-mode laser beams at both 1342 and 1050 nm are achieved from fiber-based seed oscillators and fiber amplifiers. The output power of ~25 W at 1342 nm is achieved from a single frequency fiber Raman amplifier. Output power up to 70 W at 1050 nm is achieved from a Yb-doped fiber pre-amplifier followed by a Yb-doped fiber power amplifier. For the sum frequency generation process, optimum focusing parameters are evaluated and determined. The CW system has generated more than 20 W output power at 589 nm, a circularly polarised beam with a good beam quality, spectral linewidth ≤ 2 MHz, and the laser output locked on the sodium D2 line at 589.159 nm. The system has been successfully demonstrated at EOS Space Research Centre, Mt Stromlo, Canberra, and become the Australian first working sodium guide star laser system.展开更多
Recent results in the development of diode-driven high energy, high repetition rate, picosecond lasers, including the demonstration of a cryogenic Yb:YAG active mirror amplifier that produces 1.5 J pulses at 500 Hz re...Recent results in the development of diode-driven high energy, high repetition rate, picosecond lasers, including the demonstration of a cryogenic Yb:YAG active mirror amplifier that produces 1.5 J pulses at 500 Hz repetition rate(0.75 kW average power) are reviewed. These pulses are compressed resulting in the generation of ~5 ps duration,1 J pulses with 0.5 kW average power. A full characterization of this high power cryogenic amplifier, including atwavelength interferometry of the active region under >1 kW average power pump conditions, is presented. An initial demonstration of operation at 1 kW average power(1 J, 1 k Hz) is reported.展开更多
Tailored diode laser single emitters with long(6 mm) resonators and wide(1.2 mm) emission apertures that operate with940 nm emission wavelength were assembled in novel edge-cooled vertically stacked arrays, and used t...Tailored diode laser single emitters with long(6 mm) resonators and wide(1.2 mm) emission apertures that operate with940 nm emission wavelength were assembled in novel edge-cooled vertically stacked arrays, and used to construct a compact and highly efficient fiber coupled pump source for Yb:YAG pulsed high-energy class solid-state lasers. The novel configuration is shown to allow repetition rates of 200 Hz at 1 ms pulse duration, at an output power of 130 W per single emitter. The emission of two stacked arrays was then optically combined to realize pump modules that deliver6 kW peak power(pulse energy 6 J) from a 1.9 mm core diameter fiber, with wall plug efficiency of 50%. This represents a significant improvement in terms of duty cycle and electro-optical efficiency over conventional sources. The pump module has been successfully tested at the Max Born Institute, Berlin during trials for pumping of disk lasers.展开更多
When a thin laser crystal disk is used with a nearly flat-top pump profile, the heat flux can be considered to be one-dimensional. This results in a homogeneous temperature and stress profile within the laser medium l...When a thin laser crystal disk is used with a nearly flat-top pump profile, the heat flux can be considered to be one-dimensional. This results in a homogeneous temperature and stress profile within the laser medium leading to reduction of thermal effects. A nearly flat-top pump profile is achieved with a two-pass cylindrical-lens coupling system. An average output power of 550 W is obtained by an average pumping power of 1650 W with a 40-mm diameter Nd：YAG disk. The optical-optical efficiency is 33%.展开更多
文摘A compact, efficient and high-power laser diode （LD） single-end-pumped Nd：YVO4 laser with continuous-wave emission at 1342 nm is reported. With a single crystal single-end-pumped by fibre-coupled LD array, an output power of 7.36W is obtained from the laser cavity of concave-convex shape, corresponding to an optical-to-optical efficiency of 32.8%. The laser is operated in TEM00 mode with small rms amplitude noise of 0.3%. The influences of the Nd concentration, transmissivity of the output mirror and the cavity length on the output power have been studied experimentally.
基金Fundfor Research on Doctoral Programs in Institutions of Higher Learning
文摘Diode pumped monolithic nonplanar ring laser has been developed, yielding single frequency laser and has the advantages of compactness, reliability and high efficiency. Its principles are given in detail and a monolithic nonplanar ring laser is designed. As a result, a laser of hundreds milliwatts cw single frequency output was built up, placed in a magnetic field and pumped by LD. The optical conversion efficiency was more than 15% and the slope efficiency more than 30%. The laser beam had a good quality, with M 2 about 1 2.
文摘We demonstrate an all-solid quasi-continuous-wave （QCW） narrow-band source tunable to sodium D2a line at 589.159 nm. The source is based on sum-frequency mixing between lasers at 1064 nm and 1319 nm in a LBO crystal. The 1064 nm and 1319 nm lasers are produced from two diode side-pumped Nd：YAG master oscillator power amplifier （MOPA） laser systems, respectively. A 33 W output of 589 nm laser is obtained with beam quality factor M^2 = 1.25, frequency stability better than ±0.2 GHz and linewidth less than 0.44 GHz. A prototype 589 nm laser system is assembled, and a sodium laser guided star has been successfully observed in the field test.
基金Project supported by the National Defense Pre-Research Foundation of China(Grant No.9140A020105)
文摘A novel flat-flat resonator consisting of two crystals（Nd：YAG ＋ Nd：YVO4） is established for power scaling in a diode-end-pumped solid-state laser. We systematically compare laser characteristics between multi-segmented（Nd：YAG ＋ Nd：YVO4） and conventional composite（Nd：YAG ＋ Nd：YAG） crystals to demonstrate the feasibility of spectral line matching for output power scale-up in end-pumped lasers. A maximum continuous-wave output power of 79.2 W is reported at 1064 nm, with Mx2= 4.82, My2= 5.48, and a pumping power of 136 W in the multi-segmented crystals（Nd：YAG ＋ Nd：YVO4）. Compared to conventional composite crystals（Nd：YAG ＋ Nd：YAG）, the optical-optical conversion efficiency of multi-segmented crystals（Nd：YAG ＋ Nd：YVO4） from 808 nm to 1064 nm is enhanced from 30% to 58.8%,while the laser output sensitivity as affected by the diode-laser temperature is reduced from 55% to 9%.
文摘Generation of intracavity multi-wavelength and the basic principle of sum-frequency lasers are discused, and the current research status and development of laser diode pumped lasers are introduced in detail.
基金co-financed by the European Regional Development Fundthe state budget of the Czech Republic (project HiLASE CoE: Grant No. CZ.02.1.01/0.0/ 0.0/15 006/0000674)+1 种基金the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 739573the Ministry of Education, Youth and Sports of the Czech Republic (Programmes NPU I Project No. LO1602, and Large Research Infrastructure Project No. LM2015086)
文摘Development of high energy laser sources with nanosecond pulses at several hertz values for repetition rate has been very attractive in recent years due to their great potential for practical applications. With the recent advancement in fabricating large size laser quality transparent ceramics, diode pumped solid-state laser generating pulse energy of 100 J at 10 Hz has been recently realized at HiLASE center using Yb:YAG ceramic with Cr:YAG cladding. This review discusses Yb based high energy lasers, specific laser geometries for efficient thermal management and the role of transparent ceramics in such diode pumped high-energy-class solid-state lasers around the world.
基金This work was supportedby the National Natural Science Foundation of China(No. 10474071).
文摘An efficient, stable diode-end-pumped simultaneous continuous-wave （CW） dual-wavelength laser operating at 1.319 and 1.338 ttm in a Nd：YAG crystal has been demonstrated. A total output power of 6.3 W is achieved at an absorbed pump power of 15 W, with a slope efficiency of 43.5%. The instability of output power is less than 1%. With a type II critical phase-matched KTP crystal inserted into the cavity as frequency doubler, a maximum output power of 200 mW in red region is acquired. In addition, a sixwavelength laser operation at 1.319 μm, 1.338 μm, 1.356 μm, 659.5 nm, 669 nm, and 678 nm is observed.
基金supported by the Development Fund of National Autonomous Demonstration Innovation Zone of Shandong Peninsula(Grant No.ZCQ17104)the National Key Research and Development Program of China(Grant No.2017YFB0305400)‘double hundred plan’ Yantai talent funding project
文摘A diode-pumped solid-state laser （DPSSL） with a high energetic stability and long service life is applied to ablate the steel samples instead of traditional Nd：YAG laser pumped by a xenon lamp, and several factors, such as laser pulse energy, repetition rate and argon flow rate, that influence laser-induced breakdown spectroscopy （LIBS） analytical performance are investigated in detail. Under the optimal experiment conditions, the relative standard deviations for C, Si, Mn, Ni, Cr and Cu are 3.3%-8.9%, 0.9%-2.8%, 1.2%-4.1%, 1.7%-3.0%, 1.1%-3.4% and 2.5%-8.5%, respectively, with the corresponding relative errors of 1.1%-7.9%, 1.0%-6.3%, 0.4%-3.9%, 1.5%-6.3%, 1.2%-4.0% and 1.2%-6.4%. Compared with the results of the traditional spark discharge optical emission spectrometry technique, the analytical performance of LIBS is just a little inferior due to the less stable laser-induced plasma and smaller amount of ablated sample by the laser. However, the precision, detection limits and accuracy of LIBS obtained in our present work were sufficient to meet the requirements for process analysis. These technical performances of higher stability of output energy and longer service life for DPSSL, in comparison to the Q-switch laser pumped by xeon lamp, qualify it well for the real time online analysis for different industrial applications.
基金Project supported by the National Natural Science Foundation of China （Grant Nos 60225005, 60308001, 60321003 and 60490280）.
文摘This paper demonstrates the passively mode-locked Nd：GdVO4 laser operating on the ^4F3/2-^4I9/2 transition at 912 nm by using a semiconductor saturable-absorber mirror for passive mode locking, stable continuous wave modelocked 912nm laser was achieved with a repetition rate of 176 MHz. At the incident pump power of 17.7W, 22.6mW average output power of stable mode-locked laser was obtained with a slope efficiency of 0.3%.
基金Project supported by the Program of Excellent Team in Harbin Institute of Technology, China (Grant No 60878011)
文摘This paper reports that the Tm^3＋：Lu2SiO5 （Tm：LSO） crystal is grown by Czochralski technique. The roomtemperature absorption spectra of Tm：LSO crystal are measured on a b-cut sample with 4 at.% thulium. According to the obtained Judd-Ofelt intensity parameters Ω2=9.3155×10^-20 cm^2, Ω4=8.4103×10^-20 cm^2, Ω6=1.5908×10^-20 cm^2, the fluorescence lifetime is calculated to be 2.03 ms for ^3F4 → ^3H6 transition, and the integrated emission cross section is 5.81×10^-18 cm^2. Room-temperature laser action near 2μm under diode pumping is experimentally evaluated in Tm：LSO. An optical-optical conversion efficiency of 9.1% and a slope efficiency of 16.2% are obtained with continuouswave maximum output power of 0.67 W. The emission wavelengths of Tm：LSO laser are centred around 2.06μm with spectral bandwidth of -13.6 nm.
文摘The Australian first working sodium guide star laser system has been designed and developed for various astronomical and space-related applications. A completely diode-pumped pulsed system was developed initially followed by a largely fiber-based continuous wave (CW) system operating at 589 nm achieved through a unique wavelength conversion scheme by combining 1342 and 1050 nm through a sum frequency generation process. For the CW system, single-mode laser beams at both 1342 and 1050 nm are achieved from fiber-based seed oscillators and fiber amplifiers. The output power of ~25 W at 1342 nm is achieved from a single frequency fiber Raman amplifier. Output power up to 70 W at 1050 nm is achieved from a Yb-doped fiber pre-amplifier followed by a Yb-doped fiber power amplifier. For the sum frequency generation process, optimum focusing parameters are evaluated and determined. The CW system has generated more than 20 W output power at 589 nm, a circularly polarised beam with a good beam quality, spectral linewidth ≤ 2 MHz, and the laser output locked on the sodium D2 line at 589.159 nm. The system has been successfully demonstrated at EOS Space Research Centre, Mt Stromlo, Canberra, and become the Australian first working sodium guide star laser system.
基金supported by the U.S. Department of Energy Accelerator Stewardship programme, Office of High Energy Physics, Office of Science under award DE-SC0016136support by the U.S. Department of Energy, Office of Science SBIR programme under award DE-SC0011375
文摘Recent results in the development of diode-driven high energy, high repetition rate, picosecond lasers, including the demonstration of a cryogenic Yb:YAG active mirror amplifier that produces 1.5 J pulses at 500 Hz repetition rate(0.75 kW average power) are reviewed. These pulses are compressed resulting in the generation of ~5 ps duration,1 J pulses with 0.5 kW average power. A full characterization of this high power cryogenic amplifier, including atwavelength interferometry of the active region under >1 kW average power pump conditions, is presented. An initial demonstration of operation at 1 kW average power(1 J, 1 k Hz) is reported.
基金funded in part via the European Regional Development Fund (ERDF) under contract number 20072013 2/42
文摘Tailored diode laser single emitters with long(6 mm) resonators and wide(1.2 mm) emission apertures that operate with940 nm emission wavelength were assembled in novel edge-cooled vertically stacked arrays, and used to construct a compact and highly efficient fiber coupled pump source for Yb:YAG pulsed high-energy class solid-state lasers. The novel configuration is shown to allow repetition rates of 200 Hz at 1 ms pulse duration, at an output power of 130 W per single emitter. The emission of two stacked arrays was then optically combined to realize pump modules that deliver6 kW peak power(pulse energy 6 J) from a 1.9 mm core diameter fiber, with wall plug efficiency of 50%. This represents a significant improvement in terms of duty cycle and electro-optical efficiency over conventional sources. The pump module has been successfully tested at the Max Born Institute, Berlin during trials for pumping of disk lasers.
基金This work was supported by the National "863" Program of China under Grant No. 2004AA821160.
文摘When a thin laser crystal disk is used with a nearly flat-top pump profile, the heat flux can be considered to be one-dimensional. This results in a homogeneous temperature and stress profile within the laser medium leading to reduction of thermal effects. A nearly flat-top pump profile is achieved with a two-pass cylindrical-lens coupling system. An average output power of 550 W is obtained by an average pumping power of 1650 W with a 40-mm diameter Nd：YAG disk. The optical-optical efficiency is 33%.
