Copper nanoclusters with stable compositions and precise structures have long beensought after,as they possess properties that are absent in gold and silver counterparts.However,the creation of copper nanoclusters wit...Copper nanoclusters with stable compositions and precise structures have long beensought after,as they possess properties that are absent in gold and silver counterparts.However,the creation of copper nanoclusters with novel compositions,structures,and functionalities remains largely unexplored in the literature.In this study,wedemonstrate that selenide doping is an effective method for fabricating stable coppernanostructures through controlled synthesis and structure determination of a copper–selenide nanocluster.The nanocluster of[Cu_(32)Se_(7)(BnSe)_(18)(PPh_(3))_(6)]^(+)(denoted asCu_(32)Se_(7),Bn is benzyl)has been prepared by reducing copper salts in the presenceof organic diselenides.The atomic structure of the Cu_(32)Se_(7)cluster,accurately determinedthrough single-crystal X-ray diffraction,reveals a core–shell arrangementof Cu20Se_(7)@Cu_(12)(BnSe)_(18)(PPh_(3))_(6),where Se^(2-)anions are well dispersed in theCu20 framework.Notably,this cluster represents a rare example of copper–selenidesemiconductor nanoclusters.Experimental and theoretical analysis shows stronginteractions between Se ligands and metal atoms,resulting in high stability of theCu_(32)Se_(7)cluster.Furthermore,the cluster exhibits excellent catalytic performancein the hydroboration reaction of alkynes,producing a range of vinylboron compoundswith adjustable structures and functions.Importantly,the cluster undergoesno structural or nuclearity changes during the reaction,as confirmed by extendedX-ray absorption fine structure and X-ray photoelectron spectroscopy studies.Thisstudy not only presents a molecular cluster model highlighting the effectiveness ofselenide dopants in fabricating new copper nanostructures but also paves the way forutilizing stable copper nanoclusters in diverse and exciting areas beyond catalysis.展开更多
Based on a 4f system,a 0?reflector and a single laser diode side-pump amplifier,a new amplifier is designed to compensate the spherical aberration of the amplified laser generated by a single laser diode side-pump amp...Based on a 4f system,a 0?reflector and a single laser diode side-pump amplifier,a new amplifier is designed to compensate the spherical aberration of the amplified laser generated by a single laser diode side-pump amplifier and enhance the power of the amplified laser.Furthermore,the role of the 4f system in the passive spherical aberration compensation and its effect on the amplified laser are discussed in detail.The results indicate that the amplification efficiency is enhanced by incorporating a 4f system in a double-pass amplifier and placing a 0?reflector only at the focal point of the single-pass amplified laser.This method also effectively uses the heat from the gain medium(neodymiumdoped yttrium aluminium garnet)of the amplifier to compensate the spherical aberration of the amplified laser.展开更多
In this paper,a high-power and high-efficiency 4.3μm mid-infrared(MIR)optical parametric oscillator(OPO)based on ZnGeP_(2)(ZGP)crystal is demonstrated.An acousto-optically Q-switched Ho Y_(3)Al_(5)O_(12) laser operat...In this paper,a high-power and high-efficiency 4.3μm mid-infrared(MIR)optical parametric oscillator(OPO)based on ZnGeP_(2)(ZGP)crystal is demonstrated.An acousto-optically Q-switched Ho Y_(3)Al_(5)O_(12) laser operating at 2.1μm with a maximum average output power of 35 W and pulse width of 38 ns at a repetition rate of 15 kHz is established and employed as the pump source.A doubly resonant OPO is designed and realized with the total MIR output power of 13.27 W,including the signal and idler output power of 2.65 W at 4.07μm and 10.62 W at 4.3μm.The corresponding total optical-to-optical and slope efficiencies are 37.9%and 67.1%,respectively.The shortest pulse width,beam quality factor,and output power instability are measured to be 36 ns,M_(x)^(2)=1.8,M_(y)^(2)=2.0,and RMS<1.9%at 8 h,respectively.Our results pave a way for designing high-power and high-efficiency 4–5μm MIR laser sources.展开更多
Two-dimensional(2D)ternary chalcogenides have attracted great attentions because of their novel chemical and physical properties arising from the synergistic effect and stoichiometric variation with the additional thi...Two-dimensional(2D)ternary chalcogenides have attracted great attentions because of their novel chemical and physical properties arising from the synergistic effect and stoichiometric variation with the additional third element compared with their binary counterparts.Here,high-quality 2D tantalum nickel selenide(Ta_(2)NiSe_(5))nanosheets are successfully fabricated by a liquid-phase exfoliation(LPE)method.The ultrafast excited carrier relaxation time and nonlinear optical absorption response are investigated and reveal that the prepared 2D Ta_(2)NiSe_(5)nanosheets have excellent broadband saturable absorption properties,which are further illustrated by three passively Q-switched(PQS)allsolid-state lasers operating at 1.0,2.0 and 2.8μm with the Ta_(2)NiSe_(5)nanosheet-based saturable absorber(SA).Furthermore,mode-locked laser operation with the pulse width as short as 356 fs is also realized at 1.0μm.This work not only demonstrates the excellent nonlinear optical proprieties and optical modulation performance of Ta_(2)NiSe_(5),but also paves the way for exploring the photonic and optoelectronic proprieties of ternary chalcogenide materials.展开更多
Indium phosphide(InP)nanowires(NWs)have attracted significant attention due to their exotic properties that are different from the bulk counterparts,and have been widely used for light generation,amplification,detecti...Indium phosphide(InP)nanowires(NWs)have attracted significant attention due to their exotic properties that are different from the bulk counterparts,and have been widely used for light generation,amplification,detection,modulation,and switching,etc.Here,high-quality InP NWs were directly grown on a quartz substrate by the Au-nanoparticle assisted vapor-liquid-solid method.We thoroughly studied their nonlinear optical absorption properties at 1.06μm by the open-aperture Z-scan method.Interestingly,a transition phenomenon from satu-rable absorption(SA)to reverse saturable absorption(RSA)was observed with the increase of the incident laser intensity.In the analysis,we found that the effective nonlinear absorption cofficient(βeff-10^2 cm/MW)under the SA process was 3 orders of magnitude larger than that during the RSA processes.Furthermore,the SA proper-ties of InP NWs were experimentally verified by using them as a saturable absorber for a passively Q-switched Nd:YVO4 solid-state laser at 1.06μm,where the shortest pulse width of 462 ns and largest single pulse energy of 1.32μJ were obtained.Moreover,the ultrafast carrier relaxation dynamics were basically studied,and the intraband and inter-band ultrafast carrier relaxation times of 8.1 and 63.8 ps,respectively,were measured by a degenerate pump-probe method with the probe laser of 800 nm.These results well demonstrate the nonlinear optical absorption properties,which show the excellent light manipulating capabilities of InP NWs and pave a way for their applications in ultrafast nanophotonic devices.展开更多
Stimulated Raman scattering is a third-order nonlinear optical effect that is not only effective for wavelength converting laser output, but also for single longitudinal-mode output due to the absence of spatial hole ...Stimulated Raman scattering is a third-order nonlinear optical effect that is not only effective for wavelength converting laser output, but also for single longitudinal-mode output due to the absence of spatial hole burning. Diamond is a prominent Raman-active medium that has significant potential for linewidth narrowing and wavelength converting lasers at high power levels due to its high thermal conductivity, long Raman frequency shift and wide spectral transmission range. In this work we utilize diamond in a resonantly mode-matched external cavity to achieve cascaded Raman conversion of a 1064 nm laser. By fine-tuning the length of this external cavity, we can obtain narrow linewidth emission at 1240 and 1485 nm. When operating at maximum power, the measured linewidths were more than twofold narrower than the linewidth of the fundamental field. In addition, the noise levels of the Stokes fields are lower than that of the fundamental field throughout the entire noise frequency range, and the intrinsic linewidth of the second Stokes field,which is expressed at the hertz level(~3.6 Hz), is decreased by approximately three orders of magnitude compared to that of the pump. This work represents the first measurement and analysis of the linewidth and noise characteristics of cascaded diamond Raman lasers and, significantly, offers a new means by which high-power, narrow linewidth laser output can be produced from wavelength-converted laser systems.展开更多
基金National Key R&D Program of China,Grant/Award Number:2023YFB3507100National Natural Science Foundation of China,Grant/Award Numbers:22301149,92261207+3 种基金Program for Young Talents of Science and Technology in Universities of Inner Mongolia Autonomous Region,Grant/Award Number:NJYT23035Inner Mongolia University,Grant/Award Number:10000-23112101/043NSFC Center for Single-Atom Catalysis,Grant/Award Number:22388102New Cornerstone Science Foundation。
文摘Copper nanoclusters with stable compositions and precise structures have long beensought after,as they possess properties that are absent in gold and silver counterparts.However,the creation of copper nanoclusters with novel compositions,structures,and functionalities remains largely unexplored in the literature.In this study,wedemonstrate that selenide doping is an effective method for fabricating stable coppernanostructures through controlled synthesis and structure determination of a copper–selenide nanocluster.The nanocluster of[Cu_(32)Se_(7)(BnSe)_(18)(PPh_(3))_(6)]^(+)(denoted asCu_(32)Se_(7),Bn is benzyl)has been prepared by reducing copper salts in the presenceof organic diselenides.The atomic structure of the Cu_(32)Se_(7)cluster,accurately determinedthrough single-crystal X-ray diffraction,reveals a core–shell arrangementof Cu20Se_(7)@Cu_(12)(BnSe)_(18)(PPh_(3))_(6),where Se^(2-)anions are well dispersed in theCu20 framework.Notably,this cluster represents a rare example of copper–selenidesemiconductor nanoclusters.Experimental and theoretical analysis shows stronginteractions between Se ligands and metal atoms,resulting in high stability of theCu_(32)Se_(7)cluster.Furthermore,the cluster exhibits excellent catalytic performancein the hydroboration reaction of alkynes,producing a range of vinylboron compoundswith adjustable structures and functions.Importantly,the cluster undergoesno structural or nuclearity changes during the reaction,as confirmed by extendedX-ray absorption fine structure and X-ray photoelectron spectroscopy studies.Thisstudy not only presents a molecular cluster model highlighting the effectiveness ofselenide dopants in fabricating new copper nanostructures but also paves the way forutilizing stable copper nanoclusters in diverse and exciting areas beyond catalysis.
基金supported by the National Natural Science Foundation of China(Grant Nos.62075056 and 61927815)the Natural Science Foundation of Hebei Province(Grant Nos.F2023202082 and F2022202035)。
文摘Based on a 4f system,a 0?reflector and a single laser diode side-pump amplifier,a new amplifier is designed to compensate the spherical aberration of the amplified laser generated by a single laser diode side-pump amplifier and enhance the power of the amplified laser.Furthermore,the role of the 4f system in the passive spherical aberration compensation and its effect on the amplified laser are discussed in detail.The results indicate that the amplification efficiency is enhanced by incorporating a 4f system in a double-pass amplifier and placing a 0?reflector only at the focal point of the single-pass amplified laser.This method also effectively uses the heat from the gain medium(neodymiumdoped yttrium aluminium garnet)of the amplifier to compensate the spherical aberration of the amplified laser.
基金supported by the National Key Research and Development Program of China (No. 2017YFB0405204)National Research Foundation of China (No. 61975095)+3 种基金Youth Cross Innovation Group of Shandong University (No. 2020QNQT)Development Program of Shaanxi Province(No.S2019-YF-ZDCXL-ZDLGY-0253)Major Science and Technology Innovation Project of Shandong Province (No. 2019JZZY020206)Qilu Young Scholar of Shandong University
文摘In this paper,a high-power and high-efficiency 4.3μm mid-infrared(MIR)optical parametric oscillator(OPO)based on ZnGeP_(2)(ZGP)crystal is demonstrated.An acousto-optically Q-switched Ho Y_(3)Al_(5)O_(12) laser operating at 2.1μm with a maximum average output power of 35 W and pulse width of 38 ns at a repetition rate of 15 kHz is established and employed as the pump source.A doubly resonant OPO is designed and realized with the total MIR output power of 13.27 W,including the signal and idler output power of 2.65 W at 4.07μm and 10.62 W at 4.3μm.The corresponding total optical-to-optical and slope efficiencies are 37.9%and 67.1%,respectively.The shortest pulse width,beam quality factor,and output power instability are measured to be 36 ns,M_(x)^(2)=1.8,M_(y)^(2)=2.0,and RMS<1.9%at 8 h,respectively.Our results pave a way for designing high-power and high-efficiency 4–5μm MIR laser sources.
基金financially supported by the National Natural Science Foundation of China (61975095, 61675116, and 61575110)the Young Scholars Program of Shandong University (2017WLJH48)+3 种基金the Youth Cross Innovation Group of Shandong University (2020QNQT)the Key Research and Development Program of Shandong Province (2019JZZY020206)Shenzhen Science and Technology Research and Development Funds (JCYJ20180305163932273)the Program of State Key Laboratory of Quantum Optics and Quantum Optics Devices (KF201908)
文摘Two-dimensional(2D)ternary chalcogenides have attracted great attentions because of their novel chemical and physical properties arising from the synergistic effect and stoichiometric variation with the additional third element compared with their binary counterparts.Here,high-quality 2D tantalum nickel selenide(Ta_(2)NiSe_(5))nanosheets are successfully fabricated by a liquid-phase exfoliation(LPE)method.The ultrafast excited carrier relaxation time and nonlinear optical absorption response are investigated and reveal that the prepared 2D Ta_(2)NiSe_(5)nanosheets have excellent broadband saturable absorption properties,which are further illustrated by three passively Q-switched(PQS)allsolid-state lasers operating at 1.0,2.0 and 2.8μm with the Ta_(2)NiSe_(5)nanosheet-based saturable absorber(SA).Furthermore,mode-locked laser operation with the pulse width as short as 356 fs is also realized at 1.0μm.This work not only demonstrates the excellent nonlinear optical proprieties and optical modulation performance of Ta_(2)NiSe_(5),but also paves the way for exploring the photonic and optoelectronic proprieties of ternary chalcogenide materials.
基金National Natural Science Foundation of China(61575110,61675116,61975095)Department of Science and Technology of Shandong Province(2017WLJH48)+3 种基金Shandong University(2020QNQT)Academy of Finland Photonics Flagship PREIN(320167)Walter AhLströmin SäätiöNokia.
文摘Indium phosphide(InP)nanowires(NWs)have attracted significant attention due to their exotic properties that are different from the bulk counterparts,and have been widely used for light generation,amplification,detection,modulation,and switching,etc.Here,high-quality InP NWs were directly grown on a quartz substrate by the Au-nanoparticle assisted vapor-liquid-solid method.We thoroughly studied their nonlinear optical absorption properties at 1.06μm by the open-aperture Z-scan method.Interestingly,a transition phenomenon from satu-rable absorption(SA)to reverse saturable absorption(RSA)was observed with the increase of the incident laser intensity.In the analysis,we found that the effective nonlinear absorption cofficient(βeff-10^2 cm/MW)under the SA process was 3 orders of magnitude larger than that during the RSA processes.Furthermore,the SA proper-ties of InP NWs were experimentally verified by using them as a saturable absorber for a passively Q-switched Nd:YVO4 solid-state laser at 1.06μm,where the shortest pulse width of 462 ns and largest single pulse energy of 1.32μJ were obtained.Moreover,the ultrafast carrier relaxation dynamics were basically studied,and the intraband and inter-band ultrafast carrier relaxation times of 8.1 and 63.8 ps,respectively,were measured by a degenerate pump-probe method with the probe laser of 800 nm.These results well demonstrate the nonlinear optical absorption properties,which show the excellent light manipulating capabilities of InP NWs and pave a way for their applications in ultrafast nanophotonic devices.
基金supported by the National Natural Science Foundation of China(Nos.62375076 and 61927815)the Natural Science Foundation of Tianjin City(No.22JCY-BJC01100)+2 种基金the Natural Science Foundation of Hebei Province(No.F2023202063)the Shijiazhuang Overseas Talents Introduction Project(No.20230004)the Funds for Basic Scientific Research of Hebei University of Technology(No.JBKYTD2201)
文摘Stimulated Raman scattering is a third-order nonlinear optical effect that is not only effective for wavelength converting laser output, but also for single longitudinal-mode output due to the absence of spatial hole burning. Diamond is a prominent Raman-active medium that has significant potential for linewidth narrowing and wavelength converting lasers at high power levels due to its high thermal conductivity, long Raman frequency shift and wide spectral transmission range. In this work we utilize diamond in a resonantly mode-matched external cavity to achieve cascaded Raman conversion of a 1064 nm laser. By fine-tuning the length of this external cavity, we can obtain narrow linewidth emission at 1240 and 1485 nm. When operating at maximum power, the measured linewidths were more than twofold narrower than the linewidth of the fundamental field. In addition, the noise levels of the Stokes fields are lower than that of the fundamental field throughout the entire noise frequency range, and the intrinsic linewidth of the second Stokes field,which is expressed at the hertz level(~3.6 Hz), is decreased by approximately three orders of magnitude compared to that of the pump. This work represents the first measurement and analysis of the linewidth and noise characteristics of cascaded diamond Raman lasers and, significantly, offers a new means by which high-power, narrow linewidth laser output can be produced from wavelength-converted laser systems.
