Through using both Cr^4＋：YAG and GaAs saturable absorbers, a diode-pttmped double passively Q-switched Nd：GdVO4 laser is realized and compared with a single passively Q-switched laser. This laser can generate symme...Through using both Cr^4＋：YAG and GaAs saturable absorbers, a diode-pttmped double passively Q-switched Nd：GdVO4 laser is realized and compared with a single passively Q-switched laser. This laser can generate symmetric pulse temporal profiles and shorter pulses. A laser pulse width of 17 ns has been achieved with the incident pump power of 8.5 W.展开更多
The slow degration of iron limits its bone implant application.The solid solution of Zn in Fe is expected to accelerate the degradation.In this work,mechanical alloying(MA)was used to prepare Fe-Zn powder with supersa...The slow degration of iron limits its bone implant application.The solid solution of Zn in Fe is expected to accelerate the degradation.In this work,mechanical alloying(MA)was used to prepare Fe-Zn powder with supersaturated solid solution.MA significantly decreased the lamellar spacing between particles,thus reducing the diffusion distance of solution atoms.Moreover,it caused a number of crystalline defects,which further promoted the solution diffusion.Subsequently,the MA-processed powder was consolidated into Fe-Zn part by laser sintering,which involved a partial melting/rapid solidification mechanism and retained the original supersaturated solid solution.Results proved that the Fe-Zn alloy became more susceptible with a lowered corrosion potential,and thereby an accelerated corrosion rate of(0.112±0.013)mm/year.Furthermore,it also exhibited favorable cell behavior.This work highlighted the advantage of MA combined with laser sintering for the preparation of Fe-Zn implant with improved degradation performance.展开更多
As a novel one-atom-thick carbon allotrope,graphdiyne(GDY)has attracted wide interest in two-dimensional materials owing to its unique feature with a planar layer comprising sp2-and sp-hybridized carbon atoms and a di...As a novel one-atom-thick carbon allotrope,graphdiyne(GDY)has attracted wide interest in two-dimensional materials owing to its unique feature with a planar layer comprising sp2-and sp-hybridized carbon atoms and a direct natural bandgap.A high-quality saturable absorber(SA)based on GDY was successfully fabricated,and the nonlinear saturable absorption properties were investigated.A compact diode-pumped solid-state passively Q-switched laser based on the as-prepared GDY-SA could be operated at 2µm.The Q-switched laser delivered a maximum average output power of 1.29 W at a central wavelength of 1908.41 nm with up to 54.8%slope efficiency.A repetition rate of 91.58 kHz and single pulse energy of 23.08µJ were obtained.This work is the first application of GDY as an SA to generate all-solid-state pulsed lasers.These results indicate that GDY is a promising SA for solid-state pulsed lasers and has further application potential for ultrafast photonic devices in the 2-µm region.展开更多
We demonstrate that the intrinsic properties of monolayer graphene allow it to act as a more effective saturable absorber for mode-locking fiber lasers when compared to multilayer graphene. The absorption of monolayer...We demonstrate that the intrinsic properties of monolayer graphene allow it to act as a more effective saturable absorber for mode-locking fiber lasers when compared to multilayer graphene. The absorption of monolayer graphene can be saturated at lower excitation intensity compared to multilayer graphene, graphene with wrinkle-like defects, or functionalized graphene. Monolayer graphene has a remarkably large modulation depth of 65.9%, whereas the modulation depth of multilayer graphene is greatly reduced due to nonsaturable absorption and scattering loss. Picosecond ultrafast laser pulses （1.23 ps） can be generated using monolayer graphene as a saturable absorber. Due to the ultrafast relaxation time, larger modulation depth and lower scattering loss of monolayer graphene, it performs better than multilayer graphene in terms of pulse shaping ability, pulse stability, and output energy.展开更多
A temperature sensor based on a switchable dual-wavelength fiber Bragg grating （FBG） laser with a semiconductor saturable absorber mirror （SESAM） is presented and demonstrated experimentally. The repetition rate o...A temperature sensor based on a switchable dual-wavelength fiber Bragg grating （FBG） laser with a semiconductor saturable absorber mirror （SESAM） is presented and demonstrated experimentally. The repetition rate of Q-switched pulses is -17 kHz. The results demonstrate that the measured temperature has good linearity to the wavelength spacing of the two lasing wavelengths and has a temperature sensitivity of 21 pm/℃ covering a range of-10--22 ℃. The ex- perimental results prove the feasibility of the proposed temperature sensor.展开更多
The laser trapping of untransmissive particles are discussed in this paper. Photon can generate the momentum tothe untransmissive particle by diffraction and reflection on the surface of the particles. We tried laser ...The laser trapping of untransmissive particles are discussed in this paper. Photon can generate the momentum tothe untransmissive particle by diffraction and reflection on the surface of the particles. We tried laser trapping ofuntransmissive particles using an attractive force caused by the diffraction and radiation force caused by reflection.The laser trapping system includes CW YAG laser, which has 1.064 μm in wave length and an optical microscope.The motions of particles were monitored by a CCD camera on the top of the microscope and recordedby PC connected to the CCD camera.展开更多
基金Natural Science Foundation of Shandong Province(Y2007G01).
文摘Through using both Cr^4＋：YAG and GaAs saturable absorbers, a diode-pttmped double passively Q-switched Nd：GdVO4 laser is realized and compared with a single passively Q-switched laser. This laser can generate symmetric pulse temporal profiles and shorter pulses. A laser pulse width of 17 ns has been achieved with the incident pump power of 8.5 W.
基金Projects(51935014,82072084,81871498)supported by the Natural Science Foundation of ChinaProjects(20192ACB20005,2020ACB214004)supported by the Jiangxi Provincial Natural Science Foundation of China+4 种基金Project(20201BBE51012)supported by the Provincial Key R&D Projects of Jiangxi Province,ChinaProject(2018)supported by the Guangdong Province Higher Vocational Colleges&Schools Pearl River Scholar Funded Scheme,ChinaProject(2017RS3008)supported by Hunan Provincial Science and Technology Plan,ChinaProject supported by the Open Research Fund of Jiangsu Key Laboratory of Precision and Micro-Manufacturing Technology,ChinaProject(2020M682114)China Postdoctoral Science Foundation。
文摘The slow degration of iron limits its bone implant application.The solid solution of Zn in Fe is expected to accelerate the degradation.In this work,mechanical alloying(MA)was used to prepare Fe-Zn powder with supersaturated solid solution.MA significantly decreased the lamellar spacing between particles,thus reducing the diffusion distance of solution atoms.Moreover,it caused a number of crystalline defects,which further promoted the solution diffusion.Subsequently,the MA-processed powder was consolidated into Fe-Zn part by laser sintering,which involved a partial melting/rapid solidification mechanism and retained the original supersaturated solid solution.Results proved that the Fe-Zn alloy became more susceptible with a lowered corrosion potential,and thereby an accelerated corrosion rate of(0.112±0.013)mm/year.Furthermore,it also exhibited favorable cell behavior.This work highlighted the advantage of MA combined with laser sintering for the preparation of Fe-Zn implant with improved degradation performance.
基金financially supported by the National Natural Science Foundation of China (11974220, 61635012,61875138, 61961136001, and U1801254)the State Key Research Development Program of China (2019YFB2203503)
文摘As a novel one-atom-thick carbon allotrope,graphdiyne(GDY)has attracted wide interest in two-dimensional materials owing to its unique feature with a planar layer comprising sp2-and sp-hybridized carbon atoms and a direct natural bandgap.A high-quality saturable absorber(SA)based on GDY was successfully fabricated,and the nonlinear saturable absorption properties were investigated.A compact diode-pumped solid-state passively Q-switched laser based on the as-prepared GDY-SA could be operated at 2µm.The Q-switched laser delivered a maximum average output power of 1.29 W at a central wavelength of 1908.41 nm with up to 54.8%slope efficiency.A repetition rate of 91.58 kHz and single pulse energy of 23.08µJ were obtained.This work is the first application of GDY as an SA to generate all-solid-state pulsed lasers.These results indicate that GDY is a promising SA for solid-state pulsed lasers and has further application potential for ultrafast photonic devices in the 2-µm region.
文摘We demonstrate that the intrinsic properties of monolayer graphene allow it to act as a more effective saturable absorber for mode-locking fiber lasers when compared to multilayer graphene. The absorption of monolayer graphene can be saturated at lower excitation intensity compared to multilayer graphene, graphene with wrinkle-like defects, or functionalized graphene. Monolayer graphene has a remarkably large modulation depth of 65.9%, whereas the modulation depth of multilayer graphene is greatly reduced due to nonsaturable absorption and scattering loss. Picosecond ultrafast laser pulses （1.23 ps） can be generated using monolayer graphene as a saturable absorber. Due to the ultrafast relaxation time, larger modulation depth and lower scattering loss of monolayer graphene, it performs better than multilayer graphene in terms of pulse shaping ability, pulse stability, and output energy.
基金supported by the Foundation of Hubei Provincial Department of Education of China(No.2012258)
文摘A temperature sensor based on a switchable dual-wavelength fiber Bragg grating （FBG） laser with a semiconductor saturable absorber mirror （SESAM） is presented and demonstrated experimentally. The repetition rate of Q-switched pulses is -17 kHz. The results demonstrate that the measured temperature has good linearity to the wavelength spacing of the two lasing wavelengths and has a temperature sensitivity of 21 pm/℃ covering a range of-10--22 ℃. The ex- perimental results prove the feasibility of the proposed temperature sensor.
文摘The laser trapping of untransmissive particles are discussed in this paper. Photon can generate the momentum tothe untransmissive particle by diffraction and reflection on the surface of the particles. We tried laser trapping ofuntransmissive particles using an attractive force caused by the diffraction and radiation force caused by reflection.The laser trapping system includes CW YAG laser, which has 1.064 μm in wave length and an optical microscope.The motions of particles were monitored by a CCD camera on the top of the microscope and recordedby PC connected to the CCD camera.
