Driven by their potential applications, vectorial optical fields with spatially inhomogeneous states of polarization within the cross section have drawn significant attention recently. This work intends to review some...Driven by their potential applications, vectorial optical fields with spatially inhomogeneous states of polarization within the cross section have drawn significant attention recently. This work intends to review some of the latest development of this rapidly growing field of optics and offer a general overview of the current status of this field in a few areas. Mathematical descriptions of generalized vectorial optical fields are provided along with several special examples. A time-reversal methodology for the creation of a wide variety of exotic optical focal fields with prescribed characteristics within the focal volume is presented. Recently developed methods for the generation of vectorial optical fields that utilize fiber lasers,digital lasers, vectorial optical field generator, metasurfaces or photoalignment liquid crystals are summarized. The interactions of these vectorial optical fields with various micro-and nano-structures are presented and the prospects of their potential applications are discussed. The connection of vectorial optical fields with higher dimensionality in quantum information is summarized.展开更多
Cylindrical vector beams and vortex beams,two types of typical singular optical beams characterized by axially symmetric polarization and helical phase front,possess the unique focusing property and the ability of car...Cylindrical vector beams and vortex beams,two types of typical singular optical beams characterized by axially symmetric polarization and helical phase front,possess the unique focusing property and the ability of carrying orbital angular momentum.We discuss the formation mechanisms of such singular beams in few-mode fibers under the vortex basis and show recent advances in generating techniques that are mainly based on long-period fiber gratings,mode-selective couplers,offset-spliced fibers,and tapered fibers.The performances of cylindrical vector beams and vortex beams generated in fibers and fiber lasers are summarized and compared to give a comprehensive understanding of singular beams and to promote their practical applications.展开更多
We report a method to tune the second harmonic generation(SHG) frequency of a metallic octamer by employing cylindrical vector beams as the excitation. Our method exploits the ability to spatially match the polarizati...We report a method to tune the second harmonic generation(SHG) frequency of a metallic octamer by employing cylindrical vector beams as the excitation. Our method exploits the ability to spatially match the polarization state of excitations with the fundamental target plasmonic modes, enabling flexible control of the SHG resonant frequency.It is found that SHG of the octamer is enhanced over a broad band(400 nm) by changing the excitation from the linearly polarized Gaussian beam to radially and azimuthally polarized beams. More strikingly, when subjected to an azimuthally polarized beam, the SHG intensity of the octamer becomes 30 times stronger than that for the linearly polarized beam even in the presence of Fano resonance.展开更多
In this paper, we demonstrate a scheme to tailor both longitudinal and transverse modes inside a laser cavity and constitute an eye-safe single longitudinal mode Er∶Y_(3)Al_(5)O_(12)(Er:YAG) vector laser. A q-plate i...In this paper, we demonstrate a scheme to tailor both longitudinal and transverse modes inside a laser cavity and constitute an eye-safe single longitudinal mode Er∶Y_(3)Al_(5)O_(12)(Er:YAG) vector laser. A q-plate is employed as a spin-orbital conversion element to modulate the transverse mode and obtain cylindrical vector beams. An optical isolator is employed as a nonreciprocal element for the ring cavity to enforce unidirectional operation and achieve single longitudinal oscillation. The characteristics of power, transverse intensity, and polarization spectrum of the output beams are observed. The observed typical single longitudinal mode and highly matched special polarizations prove the successful tailoring of both longitudinal and transverse modes.展开更多
A cylindrical vector beam is utilized to enhance the energy scale of the pulse post-compressed in a bulk-material Herriott multi-pass cell(MPC).The method proposed here enables,for the first time to the best of our kn...A cylindrical vector beam is utilized to enhance the energy scale of the pulse post-compressed in a bulk-material Herriott multi-pass cell(MPC).The method proposed here enables,for the first time to the best of our knowledge,pulse compression from 14 ps down to 475 fs with throughput energy beyond 1 mJ,corresponding to a compression ratio of 30,which is the highest pulse energy and compression ratio in single-stage bulk-material MPCs.Furthermore,we demonstrate the characteristic of the vector polarization beam is preserved in the MPC.展开更多
A rotating neodymium-doped yttrium aluminum garnet(Nd:YAG)disk laser resonator for efficiently generating vector beams with azimuthal and radial polarization is demonstrated.In the study,the laser crystal rotary for t...A rotating neodymium-doped yttrium aluminum garnet(Nd:YAG)disk laser resonator for efficiently generating vector beams with azimuthal and radial polarization is demonstrated.In the study,the laser crystal rotary for thermal alleviation and polarization discrimination uses c-cut ytterbium vanadate(YVO_(4)).The laser output could be switched between azimuthal and radial polarizations by simply adjusting the cavity length.The laser power reached 4.38 W and 4.64W for azimuthally and radially polarized beams at the slope efficiencies of 45.3%and 48.5%,respectively.Our study proved that an efficient,high-power vector rotary disk laser would be realistic.展开更多
With finite-element software ANSYS 7.0 and simple thermal-mechanical coupling constitutive relations,the buckling failure of preloaded cylindrical shell irradiated by high power laser beam was studied by numerical si...With finite-element software ANSYS 7.0 and simple thermal-mechanical coupling constitutive relations,the buckling failure of preloaded cylindrical shell irradiated by high power laser beam was studied by numerical simulations. The buckling mode and buckling critical loading were analysed for different preloading conditions. The influence of laser intensity, beam irradiation time, preloading conditions and geometric parameters of cylindrical shell on the buckling mode were discussed. The numerical results show that: ① the buckling deformation of the cylindrical shell was concentrated in the area of laser spot and the radial buckling was the main buckling mode, ② a linear relationship between the buckling eigenvalue and the maximum temperature at the center of laser spot was approached, ③ the buckling failure of cylindrical shell was attributed to the coupling effect of the material softening and the radial deformation in the laser spot, and hence to raise the stiffness of the material would enhance the ability for anti-irradiation of structure substantially..展开更多
As one solution to implement the largecapacity space division multiplexing(SDM)transmission systems,the mode division multiplexing(MDM)has gained much attention recently.The vector mode(VM),which is the eigenmode of t...As one solution to implement the largecapacity space division multiplexing(SDM)transmission systems,the mode division multiplexing(MDM)has gained much attention recently.The vector mode(VM),which is the eigenmode of the optical fiber,has also been adopted to realize the optical communications including the transmission over free-space optical(FSO)and optical fiber links.Considering the concerns on the short-reach optical interconnects,the low cost and high integration technologies should be developed.Direct detection(DD)with higher-order modulation formats in combination of MDM technologies could offer an available trade-off in system performance and complexity.We review demonstrations of FSO and fiber high-speed data transmission based on the VM MDM(VMDM)technologies.The special VMs,cylindrical vector beams(CVB),have been generated by the q-plate(QP)and characterized accordingly.And then they were used to implement the VMDM transmission with direct-detection orthogonal frequency division multiplexing(DD-OFDM).These demonstrations show the potential of VMDM-DD-OFDM technology in the large-capacity short-reach transmission links.展开更多
基金support provided through the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learningalso partially supported by the National Natural Science Foundation of China(91438108 and 61505062)the Chinese Scholarship Council for supporting their study at the University of Dayton through the Joint Training PhD Program and Visiting Scholar Program
文摘Driven by their potential applications, vectorial optical fields with spatially inhomogeneous states of polarization within the cross section have drawn significant attention recently. This work intends to review some of the latest development of this rapidly growing field of optics and offer a general overview of the current status of this field in a few areas. Mathematical descriptions of generalized vectorial optical fields are provided along with several special examples. A time-reversal methodology for the creation of a wide variety of exotic optical focal fields with prescribed characteristics within the focal volume is presented. Recently developed methods for the generation of vectorial optical fields that utilize fiber lasers,digital lasers, vectorial optical field generator, metasurfaces or photoalignment liquid crystals are summarized. The interactions of these vectorial optical fields with various micro-and nano-structures are presented and the prospects of their potential applications are discussed. The connection of vectorial optical fields with higher dimensionality in quantum information is summarized.
基金This work was supported by the National Key R&D Program of China(2017YFA0303800)the National Natural Science Foundation of China(11874300,11634010,61575162,61805277,61675169,91950207)+1 种基金the Fundamental Research Funds for the Central Universities(3102017AX009,3102019PY002,3102019JC008)the Natural Science Basic Research Program of Shaanxi(2018JM6013,2019JQ-447).
文摘Cylindrical vector beams and vortex beams,two types of typical singular optical beams characterized by axially symmetric polarization and helical phase front,possess the unique focusing property and the ability of carrying orbital angular momentum.We discuss the formation mechanisms of such singular beams in few-mode fibers under the vortex basis and show recent advances in generating techniques that are mainly based on long-period fiber gratings,mode-selective couplers,offset-spliced fibers,and tapered fibers.The performances of cylindrical vector beams and vortex beams generated in fibers and fiber lasers are summarized and compared to give a comprehensive understanding of singular beams and to promote their practical applications.
基金National Key R&D Program of China(2017YFA0303800)National Natural Science Foundation of China(NSFC)(11634010,51777168,61377035,61675170,61675171,61701303)+4 种基金Australian Research Council(ARC)(DP140100883)Natural Science Basic Research Plan in Shaanxi Province,China(2017JM6022)Fundamental Research Funds for the Central Universities,China(3102017zy017)Natural Science Foundation of Shanghai,China(17ZR1414300)Shanghai Pujiang Program,China(17PJ1404100)
文摘We report a method to tune the second harmonic generation(SHG) frequency of a metallic octamer by employing cylindrical vector beams as the excitation. Our method exploits the ability to spatially match the polarization state of excitations with the fundamental target plasmonic modes, enabling flexible control of the SHG resonant frequency.It is found that SHG of the octamer is enhanced over a broad band(400 nm) by changing the excitation from the linearly polarized Gaussian beam to radially and azimuthally polarized beams. More strikingly, when subjected to an azimuthally polarized beam, the SHG intensity of the octamer becomes 30 times stronger than that for the linearly polarized beam even in the presence of Fano resonance.
基金This work was supported by the National Key Research and Development Program of China(No.2017YFB0405203)National Natural Science Foundation of China(Nos.11834001 and 61905012)National Defense Basic Scientific Research Program of China(No.JCKY2020602C007)。
文摘In this paper, we demonstrate a scheme to tailor both longitudinal and transverse modes inside a laser cavity and constitute an eye-safe single longitudinal mode Er∶Y_(3)Al_(5)O_(12)(Er:YAG) vector laser. A q-plate is employed as a spin-orbital conversion element to modulate the transverse mode and obtain cylindrical vector beams. An optical isolator is employed as a nonreciprocal element for the ring cavity to enforce unidirectional operation and achieve single longitudinal oscillation. The characteristics of power, transverse intensity, and polarization spectrum of the output beams are observed. The observed typical single longitudinal mode and highly matched special polarizations prove the successful tailoring of both longitudinal and transverse modes.
文摘A cylindrical vector beam is utilized to enhance the energy scale of the pulse post-compressed in a bulk-material Herriott multi-pass cell(MPC).The method proposed here enables,for the first time to the best of our knowledge,pulse compression from 14 ps down to 475 fs with throughput energy beyond 1 mJ,corresponding to a compression ratio of 30,which is the highest pulse energy and compression ratio in single-stage bulk-material MPCs.Furthermore,we demonstrate the characteristic of the vector polarization beam is preserved in the MPC.
文摘A rotating neodymium-doped yttrium aluminum garnet(Nd:YAG)disk laser resonator for efficiently generating vector beams with azimuthal and radial polarization is demonstrated.In the study,the laser crystal rotary for thermal alleviation and polarization discrimination uses c-cut ytterbium vanadate(YVO_(4)).The laser output could be switched between azimuthal and radial polarizations by simply adjusting the cavity length.The laser power reached 4.38 W and 4.64W for azimuthally and radially polarized beams at the slope efficiencies of 45.3%and 48.5%,respectively.Our study proved that an efficient,high-power vector rotary disk laser would be realistic.
文摘With finite-element software ANSYS 7.0 and simple thermal-mechanical coupling constitutive relations,the buckling failure of preloaded cylindrical shell irradiated by high power laser beam was studied by numerical simulations. The buckling mode and buckling critical loading were analysed for different preloading conditions. The influence of laser intensity, beam irradiation time, preloading conditions and geometric parameters of cylindrical shell on the buckling mode were discussed. The numerical results show that: ① the buckling deformation of the cylindrical shell was concentrated in the area of laser spot and the radial buckling was the main buckling mode, ② a linear relationship between the buckling eigenvalue and the maximum temperature at the center of laser spot was approached, ③ the buckling failure of cylindrical shell was attributed to the coupling effect of the material softening and the radial deformation in the laser spot, and hence to raise the stiffness of the material would enhance the ability for anti-irradiation of structure substantially..
基金the National High Technology 863 Research and Development of China(No.2015AA017102)the National Natural Science Foundation of China(NSFC)(Grant Nos.61575082,61435006,61525502,and 61490715)+2 种基金the Youth Science and Technology Innovation Talents of Guangdong(No.2015TQ01X606)Guangdong Provincial Natural Science Foundation(GDSF)(No.2015A030313328)Pearl River S&T Nova Program of Guangzhou(No.201710010051).
文摘As one solution to implement the largecapacity space division multiplexing(SDM)transmission systems,the mode division multiplexing(MDM)has gained much attention recently.The vector mode(VM),which is the eigenmode of the optical fiber,has also been adopted to realize the optical communications including the transmission over free-space optical(FSO)and optical fiber links.Considering the concerns on the short-reach optical interconnects,the low cost and high integration technologies should be developed.Direct detection(DD)with higher-order modulation formats in combination of MDM technologies could offer an available trade-off in system performance and complexity.We review demonstrations of FSO and fiber high-speed data transmission based on the VM MDM(VMDM)technologies.The special VMs,cylindrical vector beams(CVB),have been generated by the q-plate(QP)and characterized accordingly.And then they were used to implement the VMDM transmission with direct-detection orthogonal frequency division multiplexing(DD-OFDM).These demonstrations show the potential of VMDM-DD-OFDM technology in the large-capacity short-reach transmission links.
