Six output wavelengths from violet to infrared have been observed simultaneously from an all-solid-state laser pumped optical parametric oscillator in a periodically poled lithium niobate crystal.The output wavelength...Six output wavelengths from violet to infrared have been observed simultaneously from an all-solid-state laser pumped optical parametric oscillator in a periodically poled lithium niobate crystal.The output wavelengths can be tuned by varying the quasi-phase matched period and/or temperature.The pump laser is a diode-pumped pasive Q-switched Nd:YVO4 laser operated at 1064nm.Using a crystal with a 29.9μm grating period,we measured six wavelengths at 448,515,532,630,773 and 1546nm and obtained efficient output.We explain the multiwavelength generation by multiwave coupling theory.This phenomenon may have novel applications in photonic devices.展开更多
A compact high power diode-pumped passively mode-locked Nd:YVO_4 laser with high repetition rate is realized.Using an Nd:YVO_4 crystal and a semiconductor saturable absorber mirror(SESAM) in the oscillator, the picose...A compact high power diode-pumped passively mode-locked Nd:YVO_4 laser with high repetition rate is realized.Using an Nd:YVO_4 crystal and a semiconductor saturable absorber mirror(SESAM) in the oscillator, the picosecond pulse output with an average power of 1.38 W, a repetition rate of 3.24 GHz, and a pulse duration of 11.4 ps is achieved. After one stage of amplification, the final output power reaches 11.34 W, corresponding to a total optical-to-optical efficiency of about 32%. The root mean square(RMS) value of power fluctuation is demonstrated to be less than 0.6% in 24 hours,showing a superior stability with the compact configuration.展开更多
The thermal effect and the heat generation in diode-end-pumped continuous-wave 914-nm Nd:YVO_4 lasers are investigated in detail.A theoretical model of a diode end-pumped solid-state laser is constructed to analyse th...The thermal effect and the heat generation in diode-end-pumped continuous-wave 914-nm Nd:YVO_4 lasers are investigated in detail.A theoretical model of a diode end-pumped solid-state laser is constructed to analyse the influence of fractional thermal loading on the thermal effect in the Nd:YVO_4 laser based on finite element analysis.The thermal focal lengths and the end-surface deformations of laser rods in Nd:YVO_4 quasi-three-level and four-level lasers are measured and compared with the results obtained by ordinary interferometry for the demonstration of higher thermal loading in 914-nm laser.Finally the fractional thermal loading in the Nd:YVO_4 quasi-three-level laser is calculated by matching the experimental and the simulated end deformations.展开更多
A diode-end-pumped electro-optic (EO) Q-switched adhesive-free bond composite Nd:YVO4 laser operating at a repetition rate of 200 kHz is reported.A pair of RbTiOPO4 (RTP) crystals are used as a high repetition EO Q-sw...A diode-end-pumped electro-optic (EO) Q-switched adhesive-free bond composite Nd:YVO4 laser operating at a repetition rate of 200 kHz is reported.A pair of RbTiOPO4 (RTP) crystals are used as a high repetition EO Q-switch.At the repetition rate of 200kHz,the maximum average output power of 11.8 W at wavelength 1064 nm and full width at half maximum of pulses of 16.65ns are achieved at an incident pump power of 27 W,corresponding to an optical conversion efficiency of 43.7% and a slope efficiency of 44.6%,respectively.To the best of our knowledge,this is the highest repetition rate reported on the EO Q-switched laser by using RTP crystals.展开更多
We observe the phenomenon of priority oscillation of the unexpected σ -polarization in high-power Nd:YVO 4 ring laser. The severe thermal lens of the σ -polarized lasing, compared with the π-polarized lasing, is th...We observe the phenomenon of priority oscillation of the unexpected σ -polarization in high-power Nd:YVO 4 ring laser. The severe thermal lens of the σ -polarized lasing, compared with the π-polarized lasing, is the only reason for the phenomenon. By designing a wedge Nd:YVO 4 crystal as the gain medium, the unexpected σ -polarization is completely suppressed in the entire range of pump powers, and the polarization stability of the expected π-polarized output is enhanced. With the output power increasing from threshold to the maximum power, no σ -polarization lasing is observed. As a result, 25.3 W of stable single-frequency laser output at 532 nm is experimentally demonstrated.展开更多
A quarter-wave plate and the thin film polarizer(TFP) are used for the LD end-pumped passively mode-locked Nd:YVO4 laser with semiconductor saturable absorber mirror(SESAM) to obtain a single beam output with a total ...A quarter-wave plate and the thin film polarizer(TFP) are used for the LD end-pumped passively mode-locked Nd:YVO4 laser with semiconductor saturable absorber mirror(SESAM) to obtain a single beam output with a total power of 4.8 W.An optical-optical efficiency is achieved to be 24% for a stable CW mode-locking operation at 1064 nm,with a pulse repetition rate of 70 MHz and pulse width of 16 ps.The multipulse in the pulse sequence is eliminated for reaching a peak power as high as 4 kW.展开更多
We presented a novel orthogonally linearly polarized Nd:YVO_4 laser.Two pieces of a-cut grown-together composite YVO_4/Nd:YVO_4 crystals were placed in the resonant cavity with the c-axis of the two crystals orthogona...We presented a novel orthogonally linearly polarized Nd:YVO_4 laser.Two pieces of a-cut grown-together composite YVO_4/Nd:YVO_4 crystals were placed in the resonant cavity with the c-axis of the two crystals orthogonally.The polarization and power performance of the orthogonally polarized laser were investigated.A 26.2-W orthogonally linearly polarized laser was obtained.The power ratio between the two orthogonally polarized lasers was varied with the pump power caused by the polarized mode coupling.The longitudinal modes competition and the corresponding variable optical beats were also observed from the orthogonally polarized laser.We also adjusted the crystals with their c-axis parallele to each other,and a 40.7-W linearly polarized TEMoo laser was obtained,and the beam quality factors were M_x^2=1.37 and M_y^2 =1.25.展开更多
A black phosphorus(BP) saturable absorber(SA) solution with different concentrations(1.0 and 0.5 mg/ml) is fabricated with the liquid-phase exfoliation method. By using the BP-SA, a compact diode-pumped passively Q-sw...A black phosphorus(BP) saturable absorber(SA) solution with different concentrations(1.0 and 0.5 mg/ml) is fabricated with the liquid-phase exfoliation method. By using the BP-SA, a compact diode-pumped passively Q-switched Nd:YVO_4 laser is demonstrated. One reflecting Bragg gratings is used as the output coupler for mode selection. By inserting those BP-SA solutions in the laser cavity, the maximum single longitude mode,Q-switched output powers of 126 mW at 692.5 kHz and 149 mW at 630.3 kHz are achieved at the pump power of 8.0 W, corresponding to the pulse durations of 144 ns and 196 ns, respectively. Moreover, longitudinal-mode characteristics of Q-switched output laser in different optical cavity lengths based on two-kind BP-SA solution concentrations are investigated. Our results show that BP-SA could also be developed as an effective SA for the Q-switched, single longitudinal mode pulse laser.展开更多
A novel flat-flat resonator consisting of two crystals(Nd:YAG + Nd:YVO_4) is established for power scaling in a diode-end-pumped solid-state laser. We systematically compare laser characteristics between multi-segment...A novel flat-flat resonator consisting of two crystals(Nd:YAG + Nd:YVO_4) is established for power scaling in a diode-end-pumped solid-state laser. We systematically compare laser characteristics between multi-segmented(Nd:YAG + Nd:YVO_4) 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 M_x^2= 4.82, M_y^2= 5.48, and a pumping power of 136 W in the multi-segmented crystals(Nd:YAG + Nd:YVO_4). 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
We report a low-noise continous-wave single-frequency Nd:YVO4 laser at 1.06μm directly pumped by an 880-nm laser diode.A maximum output power of 22 W is achieved with an optical-to-optical conversion efficiency of 46...We report a low-noise continous-wave single-frequency Nd:YVO4 laser at 1.06μm directly pumped by an 880-nm laser diode.A maximum output power of 22 W is achieved with an optical-to-optical conversion efficiency of 46.3%.The stability of the output is better than ±0.7% in the given four hours.The output beam is almost diffraction-Iimited with a measured beam quality of M^(2)_(x) =1.05 and M^(2)_(y) =1.02.The intensity noise and the phase noise of the laser reach the shot-noise limit at an analysis frequency of 5 MHz.展开更多
A high power Nd:YAG end-pumped slab amplifier chain with a Nd:YVO_4 innoslab laser as the master oscillator is demonstrated. A chain output power of 5210W with beam quality of 4 times the diffraction limit is achieved...A high power Nd:YAG end-pumped slab amplifier chain with a Nd:YVO_4 innoslab laser as the master oscillator is demonstrated. A chain output power of 5210W with beam quality of 4 times the diffraction limit is achieved by double-passing the first amplifier stage and single-passing the second stage with an optical efficiency of 29% while working at a frequency of 1 kHz and pulse width of 200μs.展开更多
基金Supported by the National Basic Research Programme of China under Grant No 2004CB619006, and the National Natural Science Foundation of China under Grant Nos 60578030 and 50590404.
文摘Six output wavelengths from violet to infrared have been observed simultaneously from an all-solid-state laser pumped optical parametric oscillator in a periodically poled lithium niobate crystal.The output wavelengths can be tuned by varying the quasi-phase matched period and/or temperature.The pump laser is a diode-pumped pasive Q-switched Nd:YVO4 laser operated at 1064nm.Using a crystal with a 29.9μm grating period,we measured six wavelengths at 448,515,532,630,773 and 1546nm and obtained efficient output.We explain the multiwavelength generation by multiwave coupling theory.This phenomenon may have novel applications in photonic devices.
基金Project supported by the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDB16030200)the National Natural Science Foundation of China(Grant Nos.11774410 and 61575217)+1 种基金the National Key Scientific Instruments Development Program of China(Grant No.2012YQ120047)the Key Research Program of Frontier Sciences of Chinese Academy of Sciences(Grant No.KJZD-EW-L11-03)
文摘A compact high power diode-pumped passively mode-locked Nd:YVO_4 laser with high repetition rate is realized.Using an Nd:YVO_4 crystal and a semiconductor saturable absorber mirror(SESAM) in the oscillator, the picosecond pulse output with an average power of 1.38 W, a repetition rate of 3.24 GHz, and a pulse duration of 11.4 ps is achieved. After one stage of amplification, the final output power reaches 11.34 W, corresponding to a total optical-to-optical efficiency of about 32%. The root mean square(RMS) value of power fluctuation is demonstrated to be less than 0.6% in 24 hours,showing a superior stability with the compact configuration.
基金supported by the National Natural Science Foundation of China (Grant No.60978016)the Technological Project of Heilongjiang Province,China (Grant No.GC06A116)the Fundamental Research Funds for the Central Universities,China (Grant No.HIT.NSRIF.201165)
文摘The thermal effect and the heat generation in diode-end-pumped continuous-wave 914-nm Nd:YVO_4 lasers are investigated in detail.A theoretical model of a diode end-pumped solid-state laser is constructed to analyse the influence of fractional thermal loading on the thermal effect in the Nd:YVO_4 laser based on finite element analysis.The thermal focal lengths and the end-surface deformations of laser rods in Nd:YVO_4 quasi-three-level and four-level lasers are measured and compared with the results obtained by ordinary interferometry for the demonstration of higher thermal loading in 914-nm laser.Finally the fractional thermal loading in the Nd:YVO_4 quasi-three-level laser is calculated by matching the experimental and the simulated end deformations.
基金Supported by the Science and Technology Department Project of Jilin Province under Grant Nos 2010PT and 20100355.
文摘A diode-end-pumped electro-optic (EO) Q-switched adhesive-free bond composite Nd:YVO4 laser operating at a repetition rate of 200 kHz is reported.A pair of RbTiOPO4 (RTP) crystals are used as a high repetition EO Q-switch.At the repetition rate of 200kHz,the maximum average output power of 11.8 W at wavelength 1064 nm and full width at half maximum of pulses of 16.65ns are achieved at an incident pump power of 27 W,corresponding to an optical conversion efficiency of 43.7% and a slope efficiency of 44.6%,respectively.To the best of our knowledge,this is the highest repetition rate reported on the EO Q-switched laser by using RTP crystals.
基金supported by the National High Technology Research and Development Program of China(Grant No.2011AA030203)the National Basic Research Program of China(Grant No.2010CB923101)+1 种基金the National Natural Science Foundation of China(Grant No.61008001)the Natural Science Foundation of Shanxi Province,China(Grant No.2011021003-2)
文摘We observe the phenomenon of priority oscillation of the unexpected σ -polarization in high-power Nd:YVO 4 ring laser. The severe thermal lens of the σ -polarized lasing, compared with the π-polarized lasing, is the only reason for the phenomenon. By designing a wedge Nd:YVO 4 crystal as the gain medium, the unexpected σ -polarization is completely suppressed in the entire range of pump powers, and the polarization stability of the expected π-polarized output is enhanced. With the output power increasing from threshold to the maximum power, no σ -polarization lasing is observed. As a result, 25.3 W of stable single-frequency laser output at 532 nm is experimentally demonstrated.
基金Project supported by the State Key Laboratory of Tribology,Tsinghua University (Grant No. SKLT08A05)
文摘A quarter-wave plate and the thin film polarizer(TFP) are used for the LD end-pumped passively mode-locked Nd:YVO4 laser with semiconductor saturable absorber mirror(SESAM) to obtain a single beam output with a total power of 4.8 W.An optical-optical efficiency is achieved to be 24% for a stable CW mode-locking operation at 1064 nm,with a pulse repetition rate of 70 MHz and pulse width of 16 ps.The multipulse in the pulse sequence is eliminated for reaching a peak power as high as 4 kW.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.50721004 and 60978032)
文摘We presented a novel orthogonally linearly polarized Nd:YVO_4 laser.Two pieces of a-cut grown-together composite YVO_4/Nd:YVO_4 crystals were placed in the resonant cavity with the c-axis of the two crystals orthogonally.The polarization and power performance of the orthogonally polarized laser were investigated.A 26.2-W orthogonally linearly polarized laser was obtained.The power ratio between the two orthogonally polarized lasers was varied with the pump power caused by the polarized mode coupling.The longitudinal modes competition and the corresponding variable optical beats were also observed from the orthogonally polarized laser.We also adjusted the crystals with their c-axis parallele to each other,and a 40.7-W linearly polarized TEMoo laser was obtained,and the beam quality factors were M_x^2=1.37 and M_y^2 =1.25.
基金Supported by West Young Scholar Foundation of the Chinese Academy of Sciences under Grant No XAB2015B27
文摘A black phosphorus(BP) saturable absorber(SA) solution with different concentrations(1.0 and 0.5 mg/ml) is fabricated with the liquid-phase exfoliation method. By using the BP-SA, a compact diode-pumped passively Q-switched Nd:YVO_4 laser is demonstrated. One reflecting Bragg gratings is used as the output coupler for mode selection. By inserting those BP-SA solutions in the laser cavity, the maximum single longitude mode,Q-switched output powers of 126 mW at 692.5 kHz and 149 mW at 630.3 kHz are achieved at the pump power of 8.0 W, corresponding to the pulse durations of 144 ns and 196 ns, respectively. Moreover, longitudinal-mode characteristics of Q-switched output laser in different optical cavity lengths based on two-kind BP-SA solution concentrations are investigated. Our results show that BP-SA could also be developed as an effective SA for the Q-switched, single longitudinal mode pulse laser.
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:YVO_4) is established for power scaling in a diode-end-pumped solid-state laser. We systematically compare laser characteristics between multi-segmented(Nd:YAG + Nd:YVO_4) 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 M_x^2= 4.82, M_y^2= 5.48, and a pumping power of 136 W in the multi-segmented crystals(Nd:YAG + Nd:YVO_4). 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%.
基金Supported by the National Natural Science Foundation of China under Grant No 60878003the National Basic Research Program of China(2010CB923101)the National High-tech R&D Program of China(2011AA030203).
文摘We report a low-noise continous-wave single-frequency Nd:YVO4 laser at 1.06μm directly pumped by an 880-nm laser diode.A maximum output power of 22 W is achieved with an optical-to-optical conversion efficiency of 46.3%.The stability of the output is better than ±0.7% in the given four hours.The output beam is almost diffraction-Iimited with a measured beam quality of M^(2)_(x) =1.05 and M^(2)_(y) =1.02.The intensity noise and the phase noise of the laser reach the shot-noise limit at an analysis frequency of 5 MHz.
文摘A high power Nd:YAG end-pumped slab amplifier chain with a Nd:YVO_4 innoslab laser as the master oscillator is demonstrated. A chain output power of 5210W with beam quality of 4 times the diffraction limit is achieved by double-passing the first amplifier stage and single-passing the second stage with an optical efficiency of 29% while working at a frequency of 1 kHz and pulse width of 200μs.
