Mode-locked lasing operations at 1064 and 910 nm wavelengths are demonstrated,respectively,in two all-fiber laser oscillators using our homemade Nd^(3+)-doped silica fiber(NDF)as the gain medium.The Al3+/Nd^(3+)co-dop...Mode-locked lasing operations at 1064 and 910 nm wavelengths are demonstrated,respectively,in two all-fiber laser oscillators using our homemade Nd^(3+)-doped silica fiber(NDF)as the gain medium.The Al3+/Nd^(3+)co-doped silica core glass was fabricated by the modified sol-gel method with 18,300×10^(-6) Nd^(3+)doping concentration.The NDF drawn by the rodin-tube method has a core of 4μm in diameter and a numerical aperture(NA)of 0.14.At 1064 nm,we measure an average laser output power of 18mWwith a pulse duration of 5.75 ps,a pulse energy of 1.14 nJ,and a slope efficiency of 7.2%.Using the same NDF gain fiber of a different length,a maximum average laser output power is 3.1 mW at 910 nm with a pulse duration of 877 ns,a pulse energy of 2.7 nJ,and a slope efficiency of 1.44%.展开更多
Large-size Al^(3+)/Nd^(3+)co-doped silica glass with 5000 ppm Nd^(3+)and 50,000 ppm Al^(3+)doping concentrations was prepared by the modified sol-gel method combined with high-temperature melting and molding technolog...Large-size Al^(3+)/Nd^(3+)co-doped silica glass with 5000 ppm Nd^(3+)and 50,000 ppm Al^(3+)doping concentrations was prepared by the modified sol-gel method combined with high-temperature melting and molding technology.Electron probe microanalyzer tests indicated that high doping homogeneity was achieved with this sample preparation method.The spectral properties of the Nd^(3+)ions were evaluated.Nd^(3+)-doped silica fiber(NDF)with a core-to-clad ratio of 20/125μm was drawn from the preform with the Al^(3+)/Nd^(3+)co-doped silica glass as the core.In the laser oscillation experiment,a maximum output power of 14.6 W at 1.06μm with a slope efficiency of 39.6%was obtained from the NDF pumped by a commercial808 nm laser diode.To the best of our knowledge,this is the highest laser power reported for an NDF operated at 1060 nm and prepared by a non-chemical vapor deposition method.In the master oscillator power amplifier experiment,a maximum power of 16.6 W corresponding to a slope efficiency of 30.5%at 1061 nm was also demonstrated.The laser performance of the NDF exhibited the great advantages and potential of the modified sol-gel method in fabricating Nd^(3+)-doped silica glass for a new type of NDFs like large mode area fibers and fibers with large diameter ratio of core/cladding.展开更多
Non-contact,self-referenced and near-infrared luminescent nanothermometers have been recognized as emerging tools in the fields of nanomedicine and nanotechnology due to their great capability of precise temperature r...Non-contact,self-referenced and near-infrared luminescent nanothermometers have been recognized as emerging tools in the fields of nanomedicine and nanotechnology due to their great capability of precise temperature readout at the nanoscale and real-time deep-tissue imaging.However,the development of multifunctional and biocompatible luminescent nanothermometers operating within the optically transparent biological windows with high thermal sensitivity(>2.0%/K)remains challenging.Here,we present(Gd0.98Nd0.02)2O3 nanothermometers operated effectively within the first and second biological windows upon continuous-wave laser diode excitation at 808 nm.Ratiometric thermometric parameters are defined by the relative changes in the emission intensities originating from the two Stark components of the 4 F3/2 level(R2 and R1)to the 4 I9/2(900-1000 nm),4 I11/2(1035-1155 nm)and 4 I13/2(1300-1450 nm)multiplets.The thermo metric parameters are evaluated for colloidal samples in a cell culture medium and powder samples,and the highest thermal sensitivity(2.18%/K at 298 K)is attained for the former in the first biological window(both the excitation and emission in the 800-965 nm range).The repeatability and temperature uncertainty are 99%and 1.2 K,respectively.The nanothermometers are biocompatible with human MNT-1 melanoma and HaCaT cells for 24 h of exposure and nanoparticle concentration up to 0.400 mg/mL,showing their potential for applications in nanomedicine,e.g.,intracellular imaging and temperature mapping.展开更多
Nd^(3+)-doped NaGdF_(4):Yb,Tm nanocrystals were synthesized by an improved high-temperature thermal decomposition method,and the effects of doping concentrations on the crystal structure,phase composition,and upconver...Nd^(3+)-doped NaGdF_(4):Yb,Tm nanocrystals were synthesized by an improved high-temperature thermal decomposition method,and the effects of doping concentrations on the crystal structure,phase composition,and upconverted fluorescence intensity were also investigated.The results reveal that the introduction of Nd^(3+) ions does not cause the transformation of the crystal phase,but induce the change of the unit cell parameters.Meanwhile,the fluorescence intensity of the synthesized nanocrystals when co-doped with 3 mol%Nd^(3+) is the strongest under the excitation of 980 nm laser,which is 3.9 times that of the Nd^(3+)-free doped nanoparticles,and the average size is 62.9 nm.And it is located in the blue area of the CIE coordinate diagram,and the corresponding color purity is 91.81%under the same experimental conditions.The resulting nanocrystals show the potential as excellent fluorescence labeling and in vivo imaging probes.展开更多
基金supported by the Key Technology Research and Development Program of Shandong Province(No.2021CXGC010202)Chinese Academy of Sciences(No.ZDBS-LY-JSC020)+1 种基金the National Key Research and Development Program of China(No.2020YFB1312802)the National Natural Science Foundation of China(Nos.61935002,62205356,and 61975216).
文摘Mode-locked lasing operations at 1064 and 910 nm wavelengths are demonstrated,respectively,in two all-fiber laser oscillators using our homemade Nd^(3+)-doped silica fiber(NDF)as the gain medium.The Al3+/Nd^(3+)co-doped silica core glass was fabricated by the modified sol-gel method with 18,300×10^(-6) Nd^(3+)doping concentration.The NDF drawn by the rodin-tube method has a core of 4μm in diameter and a numerical aperture(NA)of 0.14.At 1064 nm,we measure an average laser output power of 18mWwith a pulse duration of 5.75 ps,a pulse energy of 1.14 nJ,and a slope efficiency of 7.2%.Using the same NDF gain fiber of a different length,a maximum average laser output power is 3.1 mW at 910 nm with a pulse duration of 877 ns,a pulse energy of 2.7 nJ,and a slope efficiency of 1.44%.
基金supported by the National Natural Science Foundation of China(NSFC)(No.61975216)Zhejiang Postdoctoral Research Project(No.ZJ2020070)。
文摘Large-size Al^(3+)/Nd^(3+)co-doped silica glass with 5000 ppm Nd^(3+)and 50,000 ppm Al^(3+)doping concentrations was prepared by the modified sol-gel method combined with high-temperature melting and molding technology.Electron probe microanalyzer tests indicated that high doping homogeneity was achieved with this sample preparation method.The spectral properties of the Nd^(3+)ions were evaluated.Nd^(3+)-doped silica fiber(NDF)with a core-to-clad ratio of 20/125μm was drawn from the preform with the Al^(3+)/Nd^(3+)co-doped silica glass as the core.In the laser oscillation experiment,a maximum output power of 14.6 W at 1.06μm with a slope efficiency of 39.6%was obtained from the NDF pumped by a commercial808 nm laser diode.To the best of our knowledge,this is the highest laser power reported for an NDF operated at 1060 nm and prepared by a non-chemical vapor deposition method.In the master oscillator power amplifier experiment,a maximum power of 16.6 W corresponding to a slope efficiency of 30.5%at 1061 nm was also demonstrated.The laser performance of the NDF exhibited the great advantages and potential of the modified sol-gel method in fabricating Nd^(3+)-doped silica glass for a new type of NDFs like large mode area fibers and fibers with large diameter ratio of core/cladding.
基金Project supported by CICECO-Aveiro Institute of Materials(FCT Ref.UID/CTM/50011/2019)CESAM(Ref No.FCT UID/AMB/50017-POCI-01-0145-FEDER-007638)。
文摘Non-contact,self-referenced and near-infrared luminescent nanothermometers have been recognized as emerging tools in the fields of nanomedicine and nanotechnology due to their great capability of precise temperature readout at the nanoscale and real-time deep-tissue imaging.However,the development of multifunctional and biocompatible luminescent nanothermometers operating within the optically transparent biological windows with high thermal sensitivity(>2.0%/K)remains challenging.Here,we present(Gd0.98Nd0.02)2O3 nanothermometers operated effectively within the first and second biological windows upon continuous-wave laser diode excitation at 808 nm.Ratiometric thermometric parameters are defined by the relative changes in the emission intensities originating from the two Stark components of the 4 F3/2 level(R2 and R1)to the 4 I9/2(900-1000 nm),4 I11/2(1035-1155 nm)and 4 I13/2(1300-1450 nm)multiplets.The thermo metric parameters are evaluated for colloidal samples in a cell culture medium and powder samples,and the highest thermal sensitivity(2.18%/K at 298 K)is attained for the former in the first biological window(both the excitation and emission in the 800-965 nm range).The repeatability and temperature uncertainty are 99%and 1.2 K,respectively.The nanothermometers are biocompatible with human MNT-1 melanoma and HaCaT cells for 24 h of exposure and nanoparticle concentration up to 0.400 mg/mL,showing their potential for applications in nanomedicine,e.g.,intracellular imaging and temperature mapping.
文摘Nd^(3+)-doped NaGdF_(4):Yb,Tm nanocrystals were synthesized by an improved high-temperature thermal decomposition method,and the effects of doping concentrations on the crystal structure,phase composition,and upconverted fluorescence intensity were also investigated.The results reveal that the introduction of Nd^(3+) ions does not cause the transformation of the crystal phase,but induce the change of the unit cell parameters.Meanwhile,the fluorescence intensity of the synthesized nanocrystals when co-doped with 3 mol%Nd^(3+) is the strongest under the excitation of 980 nm laser,which is 3.9 times that of the Nd^(3+)-free doped nanoparticles,and the average size is 62.9 nm.And it is located in the blue area of the CIE coordinate diagram,and the corresponding color purity is 91.81%under the same experimental conditions.The resulting nanocrystals show the potential as excellent fluorescence labeling and in vivo imaging probes.
