A laser diode (LD) pumped Q switched high efficient intracavity frequency doubled Nd ∶YAG laser is reported here. The authors have designed an optical coupler and pointed out that the key to increasing harmonic conve...A laser diode (LD) pumped Q switched high efficient intracavity frequency doubled Nd ∶YAG laser is reported here. The authors have designed an optical coupler and pointed out that the key to increasing harmonic conversion efficiency is to decrease the loss of fundamental wave. In the experiments, a fundamental mode output laser was acquired. When the pumping power was 12 W, 2.6 W average output power at 1 064 nm with AO Q switch was obtained. 2.1 W average output power at 532 nm was obtained with intracavity frequency doubling, and the highest second harmonic conversion efficiency was 82 0 0.展开更多
We briefly review recent results on photoemission spectroscopy based on the deep and vacuum ultraviolet diode pumped solid-state lasers which we have developed.Cascaded second harmonic generation with the nonlinear cr...We briefly review recent results on photoemission spectroscopy based on the deep and vacuum ultraviolet diode pumped solid-state lasers which we have developed.Cascaded second harmonic generation with the nonlinear crystal KBe2BO3F2(KBBF)is used to generate deep ultraviolet and vacuum ultraviolet laser radiation,which complements traditional incoherent light sources such as gas discharge lamps and synchrotron radiation,and has greatly improved resolution with respect to energy,momentum,and spin of photoemission spectroscopy.Many new functions have been developed with the advantages of high photon energy,narrow linewidth,high photon flux density,and so on.These have led to the observation of various new phenomena and the amassment of new data in the fields of high temperature superconductivity,topological electronics,Fermi semi-metals,and so forth.These laser systems have revived the field of photoemission spectroscopy and provided a new platform in this frontier research field.展开更多
We report in this work a continuous wave(CW) narrowband 589 nm light generation for the purpose of laser guide assisted adaptive optics.A 39 mm long 1 mm thick periodically poled near stoichiometric LiTaO3 crystal wit...We report in this work a continuous wave(CW) narrowband 589 nm light generation for the purpose of laser guide assisted adaptive optics.A 39 mm long 1 mm thick periodically poled near stoichiometric LiTaO3 crystal with duty cycle near 50% was fabricated using electrical poling at room temperature and pumped by a Raman fiber amplifier.We tested two temperature control ovens,and a maximum conversion efficiency of about 14.3%,corresponding to 4 W of yellow light with 28 W of fundamental power,and bandwidth less than 0.18 GHz was achieved.展开更多
Exploration of new infrared(IR) nonlinear optical(NLO) materials is still in urgency owing to the indispensable roles in optoelectronic devices, resource exploration, and long-distance laser communication. The formida...Exploration of new infrared(IR) nonlinear optical(NLO) materials is still in urgency owing to the indispensable roles in optoelectronic devices, resource exploration, and long-distance laser communication. The formidable challenge is to balance the contradiction between wide band gaps and large second harmonic generation(SHG) effects in IR NLO materials. In the present work, we proposed new kinds of NLO active units, d^0 transition metal fluorooxofunctional groups for designing mid-IR NLO materials. By studying a series of d^0 transition metal oxyfluorides(TMOFs),the influences of fluorooxo-functional groups with different d^0 configuration cations on the band gap and SHG responses were explored. The results reveal that the fluorooxo-functional groups with different d^0 configuration cations can enlarge band gaps in mid-IR NLO materials. The first-principles calculations demonstrate that the nine alkali/alkaline earth metals d^0 TMOFs exhibit wide band gaps(all the band gaps >3.0 e V), large birefringence Δn(> 0.07), and two W/Mo TMOFs also exhibit large SHG responses. Moreover, by comparing with other fluorooxo-functional groups, it is found that introducing fluorine into building units is an effective way to enhance optical performance. These d^0 TMOFs with superior fluorooxo-functional groups represent a new exploration family of the mid-IR region, which sheds light on the design of mid-IR NLO materials possessing large band gap.展开更多
In this paper, a passively Q-switched and mode-locked c-cut Nd-doped vanadate crystal self-Raman laser at 1.17 μm is firstly demonstrated by using Cr4+:YAG. Two crystals of Nd3+:YVO4 and Nd3+:Gd VO4 are adopted to ge...In this paper, a passively Q-switched and mode-locked c-cut Nd-doped vanadate crystal self-Raman laser at 1.17 μm is firstly demonstrated by using Cr4+:YAG. Two crystals of Nd3+:YVO4 and Nd3+:Gd VO4 are adopted to generate laser, respectively. With the incident pump power of 13 W, the average output powers of 678 m W and 852 m W at 1.17 μm are obtained with the durations of Q-switched envelope of 1.8 ns and 2 ns, respectively. The mode-locked repetition rates are as high as 2.3 Hz and 2.2 GHz, respectively. As far as we know, the Q-switched envelope is the narrowest and the mode-locked repetition rate is the highest at present in this field. In addition, yellow laser output is also achieved by using the Li B3O5 frequency doubling crystal.展开更多
文摘A laser diode (LD) pumped Q switched high efficient intracavity frequency doubled Nd ∶YAG laser is reported here. The authors have designed an optical coupler and pointed out that the key to increasing harmonic conversion efficiency is to decrease the loss of fundamental wave. In the experiments, a fundamental mode output laser was acquired. When the pumping power was 12 W, 2.6 W average output power at 1 064 nm with AO Q switch was obtained. 2.1 W average output power at 532 nm was obtained with intracavity frequency doubling, and the highest second harmonic conversion efficiency was 82 0 0.
基金Project supported by the National Development Project for Major Scientific Research Facility(No.ZDYZ2012-2)the National Instrumentation Program(No.2012YQ120048)
文摘We briefly review recent results on photoemission spectroscopy based on the deep and vacuum ultraviolet diode pumped solid-state lasers which we have developed.Cascaded second harmonic generation with the nonlinear crystal KBe2BO3F2(KBBF)is used to generate deep ultraviolet and vacuum ultraviolet laser radiation,which complements traditional incoherent light sources such as gas discharge lamps and synchrotron radiation,and has greatly improved resolution with respect to energy,momentum,and spin of photoemission spectroscopy.Many new functions have been developed with the advantages of high photon energy,narrow linewidth,high photon flux density,and so on.These have led to the observation of various new phenomena and the amassment of new data in the fields of high temperature superconductivity,topological electronics,Fermi semi-metals,and so forth.These laser systems have revived the field of photoemission spectroscopy and provided a new platform in this frontier research field.
基金supported by the National Natural Science Foundation of China (Grant Nos. 11004025,11174046,11104131)
文摘We report in this work a continuous wave(CW) narrowband 589 nm light generation for the purpose of laser guide assisted adaptive optics.A 39 mm long 1 mm thick periodically poled near stoichiometric LiTaO3 crystal with duty cycle near 50% was fabricated using electrical poling at room temperature and pumped by a Raman fiber amplifier.We tested two temperature control ovens,and a maximum conversion efficiency of about 14.3%,corresponding to 4 W of yellow light with 28 W of fundamental power,and bandwidth less than 0.18 GHz was achieved.
基金supported by Tianshan Innovation Team Program (2018D14001)the National Natural Science Foundation of China (51922014 and 11774414)+2 种基金Shanghai Cooperation Organization Science and Technology Partnership Program (2017E01013)Xinjiang Program of Introducing High-Level Talents, Fujian Institute of Innovation, Chinese Academy of Sciences (FJCXY18010202)the Western Light Foundation of CAS (2017-XBQNXZ-B-006 and 2016QNXZ-B-9)
文摘Exploration of new infrared(IR) nonlinear optical(NLO) materials is still in urgency owing to the indispensable roles in optoelectronic devices, resource exploration, and long-distance laser communication. The formidable challenge is to balance the contradiction between wide band gaps and large second harmonic generation(SHG) effects in IR NLO materials. In the present work, we proposed new kinds of NLO active units, d^0 transition metal fluorooxofunctional groups for designing mid-IR NLO materials. By studying a series of d^0 transition metal oxyfluorides(TMOFs),the influences of fluorooxo-functional groups with different d^0 configuration cations on the band gap and SHG responses were explored. The results reveal that the fluorooxo-functional groups with different d^0 configuration cations can enlarge band gaps in mid-IR NLO materials. The first-principles calculations demonstrate that the nine alkali/alkaline earth metals d^0 TMOFs exhibit wide band gaps(all the band gaps >3.0 e V), large birefringence Δn(> 0.07), and two W/Mo TMOFs also exhibit large SHG responses. Moreover, by comparing with other fluorooxo-functional groups, it is found that introducing fluorine into building units is an effective way to enhance optical performance. These d^0 TMOFs with superior fluorooxo-functional groups represent a new exploration family of the mid-IR region, which sheds light on the design of mid-IR NLO materials possessing large band gap.
基金supported by the National Natural Science Foundation of China(No.61108021)the Beijing Natural Science Foundation(No.4102048)the Fundamental Research Funds for the Central Universities(No.2013JBM091)
文摘In this paper, a passively Q-switched and mode-locked c-cut Nd-doped vanadate crystal self-Raman laser at 1.17 μm is firstly demonstrated by using Cr4+:YAG. Two crystals of Nd3+:YVO4 and Nd3+:Gd VO4 are adopted to generate laser, respectively. With the incident pump power of 13 W, the average output powers of 678 m W and 852 m W at 1.17 μm are obtained with the durations of Q-switched envelope of 1.8 ns and 2 ns, respectively. The mode-locked repetition rates are as high as 2.3 Hz and 2.2 GHz, respectively. As far as we know, the Q-switched envelope is the narrowest and the mode-locked repetition rate is the highest at present in this field. In addition, yellow laser output is also achieved by using the Li B3O5 frequency doubling crystal.