We demonstrate a high-power single-frequency diode-side pumped Nd:YAG laser at 1064 nm.A bow-tie ring cavity configuration comprising two plane and two curved mirrors with two-rod birefringence compensation is employe...We demonstrate a high-power single-frequency diode-side pumped Nd:YAG laser at 1064 nm.A bow-tie ring cavity configuration comprising two plane and two curved mirrors with two-rod birefringence compensation is employed.The influence of length Lx between two curved mirrors on output power and beam quality is investigated theoretically and experimentally while the separation of the flat mirrors is set to be 656 mm and the fold angle is 10°.When the pump powers are 358,343 and 329 W at 808 nm,the maximal output powers of 31.9,26 and 14.1 W are obtained with beam quality factors M2=1.41,1.12 and 1.20 for Lx=205,215 and 230 mm,respectively.展开更多
We report a high power high beam quality quasi-continuous-wave(QCW)diode-end-pumped Nd:YAG slab amplifier at 1319 nm.The strongest 1064 nm parasitic oscillation has been successfully suppressed by reasonable coating d...We report a high power high beam quality quasi-continuous-wave(QCW)diode-end-pumped Nd:YAG slab amplifier at 1319 nm.The strongest 1064 nm parasitic oscillation has been successfully suppressed by reasonable coating design.In a five-pass configuration,the amplifier yields a 42.3 W linearly polarized 1319 nm output at repetition rate of 1 kHz with pulse duration of 75μs and beam quality factors of M^(2)_(x)=1.13 and M^(2)_(y)=2.16 in the orthogonal directions.The fluctuation of the amplifier output power is measured to be±0.6%.Furthermore,a computational model of QCW pulse amplification is employed to examine the amplification process.展开更多
A 785 nm diode-side-pumped high-power high-pulse-repetition-frequency Q-switched 2 μm Tm:YAG laser system is reported.Under a pump power of 1300 W,a 171.4 W average output power is achieved at a pulse repetition freq...A 785 nm diode-side-pumped high-power high-pulse-repetition-frequency Q-switched 2 μm Tm:YAG laser system is reported.Under a pump power of 1300 W,a 171.4 W average output power is achieved at a pulse repetition frequency of 10 kHz.To our knowledge,this is the highest average output power for a diode-pumped all solid-state Q-switched 2 μm Tm:YAG laser.The laser output corresponds to an optical-to-optical conversion efficiency of 13.3% and a slope efficiency of 18.9%.展开更多
We report a compact high power Tm,Ho：YAG laser nearly at room temperature. The laser-diode side-pumped Tm：YAG and Tm,Ho：YAG laser modules are operated in the same cavity. The laser yields 37.34 W of continuous wave...We report a compact high power Tm,Ho：YAG laser nearly at room temperature. The laser-diode side-pumped Tm：YAG and Tm,Ho：YAG laser modules are operated in the same cavity. The laser yields 37.34 W of continuous wave output power under the temperature of 6℃, corresponding to a maximum slope efficiency of 16.7% when the output power lies from 5.1 W to 27.0 W. This is the first report on the combined Tm：YAG and Tm,Ho：YAG lasers for obtaining high power 2.1 μm laser.展开更多
Tomographic imaging and three-dimensional reconstruction based on a high-gain picosecond optical parametric amplifier (OPA) is demonstrated. More than 40dB intensity amplification of the image is achieved from the hig...Tomographic imaging and three-dimensional reconstruction based on a high-gain picosecond optical parametric amplifier (OPA) is demonstrated. More than 40dB intensity amplification of the image is achieved from the high-gain OPA.The images of various longitudinal positions of the target are extracted by the gated nature of the OPA,then a three-dimensional (3-D) surface topography of the target is reconstructed.The gated and high-gain property of the OPA allows tomographic optical imaging together with 3-D profile reconstruction of the target in turbid media.展开更多
A diode-side-pumped Nd:YAG ceramic slab laser with a high power output is presented.An average power of 526 W is achieved at 1064 nm with a repetition rate of 120 Hz and a pulse width of 180µs from a 93mm×52...A diode-side-pumped Nd:YAG ceramic slab laser with a high power output is presented.An average power of 526 W is achieved at 1064 nm with a repetition rate of 120 Hz and a pulse width of 180µs from a 93mm×52mm×8mm ceramic slab at a pump power of 1928 W,corresponding to an optical-to-optical efficiency of 27.3%.展开更多
Superconducting MgB_(2) thin films were fabricated on Al_(2)O_(3)(0001)substrates under an ex situ processing conditions.Boron thin films were deposited by pulsed laser deposition followed by a post-annealing process....Superconducting MgB_(2) thin films were fabricated on Al_(2)O_(3)(0001)substrates under an ex situ processing conditions.Boron thin films were deposited by pulsed laser deposition followed by a post-annealing process.Resistance measurements of the deposited MgB_(2) films show Tc of~39 K,while scanning electron microscopy and x-ray diffraction analysis indicate that the films consist of well-crystallized grains with a highly c-axis-oriented structure.展开更多
Atomically regulated unit-cell by unit-cell homoepitaxial SrTiO_(3) and heteroepitaxial BaTiO_(3) films were fabricated on SrTiO_(3)(100)substrates by laser molecular beam epitaxy.The fine streak patterns and more tha...Atomically regulated unit-cell by unit-cell homoepitaxial SrTiO_(3) and heteroepitaxial BaTiO_(3) films were fabricated on SrTiO_(3)(100)substrates by laser molecular beam epitaxy.The fine streak patterns and more than 1000 cycles undamping intensity oscillation were obtained by in situ reflection high-energy electron diffraction with precisely controlled intermittence between each unit-cell layer.The surface morphology of the films was examined by atomic force microscopy.The root-mean-square surface roughness of the films is about 0.1 nm.展开更多
A pyrometric absorption method suitable for strongly absorbing films has been developed to monitor the YBa_(2)Cu_(3)O_(7-δ)film growth.This method makes use of the temperature difference between the heater and the su...A pyrometric absorption method suitable for strongly absorbing films has been developed to monitor the YBa_(2)Cu_(3)O_(7-δ)film growth.This method makes use of the temperature difference between the heater and the substrate.By deducing the absorption formula of radiation light and fitting it to the radiation intensity data measured,it is possible to monitor the film thickness and the film surface temperature during deposition.Experimental results show that this is a simple and practicable method.展开更多
Laser molecular beam epitaxy(laser MBE)technique was utilized to grow the barium titanate(BaTiO_(3),BTO)thin films on SrTiO_(3)(100)substrates.The surface morphology of the BaTiO_(3) thin films was studied by atomic f...Laser molecular beam epitaxy(laser MBE)technique was utilized to grow the barium titanate(BaTiO_(3),BTO)thin films on SrTiO_(3)(100)substrates.The surface morphology of the BaTiO_(3) thin films was studied by atomic force microscopy(AFM).Two-and three-dimensional AFM images were obtained.The root mean square surface roughness,the height profile,the histogram and the bearing ratio of the height distributions for the BaTiO_(3) thin films were analyzed in detail.The results indicate that the laser MBE thin films exhibit an atomically smooth surface.展开更多
The polarization dependence of conduction inf ersubband transitions in GaAs/AlGaAs step multiqua.ntum well structures hasJbeen studied using infrared spectroscopy.For S-polarized 45°oblique angle incidence config...The polarization dependence of conduction inf ersubband transitions in GaAs/AlGaAs step multiqua.ntum well structures hasJbeen studied using infrared spectroscopy.For S-polarized 45°oblique angle incidence configuration with respect to sample surface normal,the transverse electric(TE)active intersubband transitions were observed.Both transverse electric and transverse magnetic(TM)active intersubband transitions were obtained in P-polarized incidence at 45°angle on sample,which shows a small energy splitting between TE and TM absorption peaks.展开更多
BaTiO_(3)(BTO)/YBa_(2)Cu_(3)O_(7) (YBCO) heteroepitaxial films have been fabricated on (100) SrTiO_(3) substrates by pulsed laser ablation. X-ray characterizations show the BTO/YBCO bilayer films have a highly epitaxi...BaTiO_(3)(BTO)/YBa_(2)Cu_(3)O_(7) (YBCO) heteroepitaxial films have been fabricated on (100) SrTiO_(3) substrates by pulsed laser ablation. X-ray characterizations show the BTO/YBCO bilayer films have a highly epitaxial nature. Rocking curves for the BTO (002) and YBCO (005) peaks have full width at half maximum values of 0.36°and 0.32°, respectively. The Ф scan plots indicate good in-plane alignments of these epitaxial films. The ferroelectric properties of the B TO/YBCO heteroepitaxial films were evaluated by capacitance-voltage measurement in metal-ferroelectric-metal configuration.展开更多
基金by the National Basic Research Program of China under Grant No 2010CB630706the National High Technology Research and Development Program+1 种基金the National Natural Science Foundation of Chinathe Knowledge Innovation Program of Chinese Academy of Sciences。
文摘We demonstrate a high-power single-frequency diode-side pumped Nd:YAG laser at 1064 nm.A bow-tie ring cavity configuration comprising two plane and two curved mirrors with two-rod birefringence compensation is employed.The influence of length Lx between two curved mirrors on output power and beam quality is investigated theoretically and experimentally while the separation of the flat mirrors is set to be 656 mm and the fold angle is 10°.When the pump powers are 358,343 and 329 W at 808 nm,the maximal output powers of 31.9,26 and 14.1 W are obtained with beam quality factors M2=1.41,1.12 and 1.20 for Lx=205,215 and 230 mm,respectively.
基金Supported by the National Basic Research Program of China under Grant No 2010CB630706the National High-Technology Research and Development Program under Grant No 2011AA030202the National Natural Science Foundation of China under Grant No 50990304.
文摘We report a high power high beam quality quasi-continuous-wave(QCW)diode-end-pumped Nd:YAG slab amplifier at 1319 nm.The strongest 1064 nm parasitic oscillation has been successfully suppressed by reasonable coating design.In a five-pass configuration,the amplifier yields a 42.3 W linearly polarized 1319 nm output at repetition rate of 1 kHz with pulse duration of 75μs and beam quality factors of M^(2)_(x)=1.13 and M^(2)_(y)=2.16 in the orthogonal directions.The fluctuation of the amplifier output power is measured to be±0.6%.Furthermore,a computational model of QCW pulse amplification is employed to examine the amplification process.
基金Supported by the National High-Technology Research and Development Program of Chinathe National Basic Research Pro-gram of China,the National Natural Science Foundation of Chinathe Knowledge Innovation Program of Chinese Academy of Sciences.
文摘A 785 nm diode-side-pumped high-power high-pulse-repetition-frequency Q-switched 2 μm Tm:YAG laser system is reported.Under a pump power of 1300 W,a 171.4 W average output power is achieved at a pulse repetition frequency of 10 kHz.To our knowledge,this is the highest average output power for a diode-pumped all solid-state Q-switched 2 μm Tm:YAG laser.The laser output corresponds to an optical-to-optical conversion efficiency of 13.3% and a slope efficiency of 18.9%.
文摘We report a compact high power Tm,Ho：YAG laser nearly at room temperature. The laser-diode side-pumped Tm：YAG and Tm,Ho：YAG laser modules are operated in the same cavity. The laser yields 37.34 W of continuous wave output power under the temperature of 6℃, corresponding to a maximum slope efficiency of 16.7% when the output power lies from 5.1 W to 27.0 W. This is the first report on the combined Tm：YAG and Tm,Ho：YAG lasers for obtaining high power 2.1 μm laser.
文摘Tomographic imaging and three-dimensional reconstruction based on a high-gain picosecond optical parametric amplifier (OPA) is demonstrated. More than 40dB intensity amplification of the image is achieved from the high-gain OPA.The images of various longitudinal positions of the target are extracted by the gated nature of the OPA,then a three-dimensional (3-D) surface topography of the target is reconstructed.The gated and high-gain property of the OPA allows tomographic optical imaging together with 3-D profile reconstruction of the target in turbid media.
基金by the Major Program of the National Natural Science Foundation of China under Grant No 50990304the Natural Science Foundation of Shanghai under Grant No 09ZR1435600.
文摘A diode-side-pumped Nd:YAG ceramic slab laser with a high power output is presented.An average power of 526 W is achieved at 1064 nm with a repetition rate of 120 Hz and a pulse width of 180µs from a 93mm×52mm×8mm ceramic slab at a pump power of 1928 W,corresponding to an optical-to-optical efficiency of 27.3%.
基金Supported by a grant from the State Kay Program of China and the National Natural Science Foundation of China.
文摘Superconducting MgB_(2) thin films were fabricated on Al_(2)O_(3)(0001)substrates under an ex situ processing conditions.Boron thin films were deposited by pulsed laser deposition followed by a post-annealing process.Resistance measurements of the deposited MgB_(2) films show Tc of~39 K,while scanning electron microscopy and x-ray diffraction analysis indicate that the films consist of well-crystallized grains with a highly c-axis-oriented structure.
基金Supported by the National Natural Science Foundation of China under Grant Nos.69437010 and 59392800the Chinese Academy of Sciencesthe National Centre for R&D on Superconductivity of China.
文摘Atomically regulated unit-cell by unit-cell homoepitaxial SrTiO_(3) and heteroepitaxial BaTiO_(3) films were fabricated on SrTiO_(3)(100)substrates by laser molecular beam epitaxy.The fine streak patterns and more than 1000 cycles undamping intensity oscillation were obtained by in situ reflection high-energy electron diffraction with precisely controlled intermittence between each unit-cell layer.The surface morphology of the films was examined by atomic force microscopy.The root-mean-square surface roughness of the films is about 0.1 nm.
基金Supported by the National Centre for Research and Development on Superconductor of China.
文摘A pyrometric absorption method suitable for strongly absorbing films has been developed to monitor the YBa_(2)Cu_(3)O_(7-δ)film growth.This method makes use of the temperature difference between the heater and the substrate.By deducing the absorption formula of radiation light and fitting it to the radiation intensity data measured,it is possible to monitor the film thickness and the film surface temperature during deposition.Experimental results show that this is a simple and practicable method.
基金Supported by the National Natural Science Foundation of China under Grant Nos.59392800 and 69437101the Chinese Academy of Sciences,the National Superconducting Research Center,and the Research Grant No.94-189 RG/PHYS/AS of the Third World Academy of Sciences.
文摘Laser molecular beam epitaxy(laser MBE)technique was utilized to grow the barium titanate(BaTiO_(3),BTO)thin films on SrTiO_(3)(100)substrates.The surface morphology of the BaTiO_(3) thin films was studied by atomic force microscopy(AFM).Two-and three-dimensional AFM images were obtained.The root mean square surface roughness,the height profile,the histogram and the bearing ratio of the height distributions for the BaTiO_(3) thin films were analyzed in detail.The results indicate that the laser MBE thin films exhibit an atomically smooth surface.
基金Supported by the National Natural Science Foundation of China.
文摘The polarization dependence of conduction inf ersubband transitions in GaAs/AlGaAs step multiqua.ntum well structures hasJbeen studied using infrared spectroscopy.For S-polarized 45°oblique angle incidence configuration with respect to sample surface normal,the transverse electric(TE)active intersubband transitions were observed.Both transverse electric and transverse magnetic(TM)active intersubband transitions were obtained in P-polarized incidence at 45°angle on sample,which shows a small energy splitting between TE and TM absorption peaks.
基金the National Natural Science Foundation of China.
文摘BaTiO_(3)(BTO)/YBa_(2)Cu_(3)O_(7) (YBCO) heteroepitaxial films have been fabricated on (100) SrTiO_(3) substrates by pulsed laser ablation. X-ray characterizations show the BTO/YBCO bilayer films have a highly epitaxial nature. Rocking curves for the BTO (002) and YBCO (005) peaks have full width at half maximum values of 0.36°and 0.32°, respectively. The Ф scan plots indicate good in-plane alignments of these epitaxial films. The ferroelectric properties of the B TO/YBCO heteroepitaxial films were evaluated by capacitance-voltage measurement in metal-ferroelectric-metal configuration.
