An optical vortex having an isolated point singularity is associated with the spatial structure of light waves.A polarization vortex(vector beam) with a polarization singularity has spatially variant polarizations. A ...An optical vortex having an isolated point singularity is associated with the spatial structure of light waves.A polarization vortex(vector beam) with a polarization singularity has spatially variant polarizations. A phase vortex with phase singularity or screw dislocation has a spiral phase front. The optical vortex has recently gained increasing interest in optical trapping, optical tweezers, laser machining, microscopy, quantum information processing, and optical communications. In this paper, we review recent advances in optical communications using optical vortices. First, basic concepts of polarization/phase vortex modulation and multiplexing in communications and key techniques of polarization/phase vortex generation and(de)multiplexing are introduced. Second, free-space and fiber optical communications using optical vortex modulation and optical vortex multiplexing are presented. Finally, key challenges and perspectives of optical communications using optical vortices are discussed. It is expected that optical vortices exploiting the space physical dimension of light waves might find more interesting applications in optical communications and interconnects.展开更多
We demonstrate that the combination of digital spiral imaging with high-dimensional orbital angular momentum(OAM)entanglement can be used for efficiently probing and identifying pure phase objects,where the probing li...We demonstrate that the combination of digital spiral imaging with high-dimensional orbital angular momentum(OAM)entanglement can be used for efficiently probing and identifying pure phase objects,where the probing light does not necessarily touch the object,via the experimental,non-local decomposition of non-integer pure phase vortices in OAM-entangled photon pairs.The entangled photons are generated by parametric downconversion and then measured with spatial light modulators and single-mode fibers.The fractional phase vortices are defined in the idler photons,while their corresponding spiral spectra are obtained non-locally by scanning the measured OAM states in the signal photons.We conceptually illustrate our results with the biphoton Klyshko picture and the effective dimensionality to demonstrate the high-dimensional nature of the associated quantum OAM channels.Our result is a proof of concept that quantum imaging techniques exploiting high-dimensional entanglement can potentially be used for remote sensing.展开更多
Optical vortices carrying orbital angular momentum(OAM)have attracted increasing interest in recent years.Optical vortices have seen a variety of emerging applications in optical manipulation,optical trapping,optical ...Optical vortices carrying orbital angular momentum(OAM)have attracted increasing interest in recent years.Optical vortices have seen a variety of emerging applications in optical manipulation,optical trapping,optical tweezers,optical vortex knots,imaging,microscopy,sensing,metrology,quantum information processing,and optical communications.In various optical vortices enabled applications,the generation of multiple optical vortices is of great importance.In this review article,we focus on the methods of multiple optical vortices generation and its applications.We review the methods for generating multiple optical vortices in three cases,i.e.,1-to-N collinear OAM modes,1-to-N OAM mode array and N-to-N collinear OAM modes.Diverse applications of multiple OAM modes in optical communications and non-communication areas are presented.Future trends,perspectives and opportunities are also discussed.展开更多
The generation and manipulation of optical vortices are of fundamental importance in a variety of promising applications. Here, we develop a nonlinear optical paradigm to implement self- and cross-convolution of optic...The generation and manipulation of optical vortices are of fundamental importance in a variety of promising applications. Here, we develop a nonlinear optical paradigm to implement self- and cross-convolution of optical vortex arrays, demonstrating the features of a vortex copier and regenerator. We use a phase-only spatial light modulator to prepare the 1064 nm invisible fundamental light to carry special optical vortex arrays and use a potassium titanyl phosphate crystal to perform type Ⅱ second-harmonic generation in the Fourier domain to achieve 532 nm visible structured vortices. Based on pure cross-convolution, we succeed in copying arbitrary-order single vortices as well as their superposition states onto a prearranged array of fundamental Gaussian spots. Also, based on the simultaneous effect of self- and cross-convolutions, we can expand the initial vortex lattices to regenerate more vortices carrying various higher topological charges. Our presented method of realizing imaging, an optical vortex copier and regenerator could find direct applications in optical mani optical communication, and quantum information processing with structured vortex pulation, optical arrays.展开更多
Non-spreading nature of Bessel spatiotemporal wavepackets is theoretically and experimentally investigated and orders of magnitude improvement in the spatiotemporal spreading has been demonstrated.The spatiotemporal c...Non-spreading nature of Bessel spatiotemporal wavepackets is theoretically and experimentally investigated and orders of magnitude improvement in the spatiotemporal spreading has been demonstrated.The spatiotemporal confinement provided by the Bessel spatiotemporal wavepacket is further exploited to transport transverse orbital angular momentum through embedding spatiotemporal optical vortex into the Bessel spatiotemporal wavepacket, constructing a new type of wavepacket: Bessel spatiotemporal optical vortex. Both numerical and experimental results demonstrate that spatiotemporal vortex structure can be well maintained and confined through much longer propagation. High order spatiotemporal optical vortices can also be better confined in the spatiotemporal domain and prevented from further breaking up, overcoming a potential major obstacle for future applications of spatiotemporal vortex.展开更多
This paper introduces a novel method to realize the superposition of orbital angular momentum of photons by combined computer-generated hologram （CCGH） fabricated in silica glass with femtosecond laser pulses. First...This paper introduces a novel method to realize the superposition of orbital angular momentum of photons by combined computer-generated hologram （CCGH） fabricated in silica glass with femtosecond laser pulses. Firstly, the two computer-generated holograms （CGH） of optical vortex were obtained and combined as a CCGH according to the design. Then the CCGH was directly written inside glass by femtosecond laser pulses induced microexplosion without any preor post-treatment of the material. The vortex beams with different vortex topological charges （including new topological charges） have been restructured using a collimated He-Ne laser beam incidence to the CCGH normally. A theoretical and experimental explanation has been presented for the generations of the new topological charges.展开更多
Spatiotemporal optical vortex(STOV)pulses can carry transverse orbital angular momentum(OAM)that is perpendicular to the direction of pulse propagation.For a STOV pulse,its spatiotemporal profile can be significantly ...Spatiotemporal optical vortex(STOV)pulses can carry transverse orbital angular momentum(OAM)that is perpendicular to the direction of pulse propagation.For a STOV pulse,its spatiotemporal profile can be significantly distorted due to unbalanced dispersive and diffractive phases.This may limit its use in many research applications,where a long interaction length and a tight confinement of the pulse are needed.The first demonstration of STOV pulse propagation through a few-mode optical fiber is presented.Both numerical and experimental analysis on the propagation of STOV pulse through a commercially available SMF-28 standard telecommunication fiber is performed.The spatiotemporal phase feature of the pulse can be well kept after the pulse propagates a few-meter length through the fiber even with bending.Further propagation of the pulse will result in a breakup of its spatiotemporal spiral phase structure due to an excessive amount of modal group delay dispersion.The stable and robust transmission of transverse photonic OAM through optical fiber may open new opportunities for transverse photonic OAM studies in telecommunications,OAM lasers,and nonlinear fiber-optical research.展开更多
High-order Laguerre–Gaussian(LG)petal-like beams have become a topic of significant interest due to their potential application in next-generation optical trapping,quantum optics,and materials processing technologies...High-order Laguerre–Gaussian(LG)petal-like beams have become a topic of significant interest due to their potential application in next-generation optical trapping,quantum optics,and materials processing technologies.In this work,we demonstrate the generation of high-order LG beams with petal-like spatial profiles and tunable orbital angular momentum(OAM)in the mid-infrared wavelength region.These beams are generated using idler-resonant optical parametric oscillation(OPO)in a KTiOAsO_(4)(KTA)crystal.By adjusting the length of the resonant cavity,the OAM of the mid-infrared idler field can be tuned and we demonstrate tuning in the range of 0 to10.When using a maximum pump energy of 20.2 mJ,the maximum output energy of high-order modes LG_(0.45),LG_(0.48),and LG_(0.410) were 0.8,0.53,and 0.46 mJ,respectively.The means by which high-order LG modes with petal-like spatial profiles and tunable OAM were generated from the OPO is theoretically modeled by examining the spatial overlap efficiency of the beam waists of the pump and resonant idler fields within the center of the KTA crystal.The methodology presented in this work offers a simple and flexible method to wavelength-convert laser emission and generate high-order LG modes.展开更多
Recognized in the 1990s,vortex beams'ability to carry orbital angular momentum(OAM)has significantly contributed to applications in optical manipulation and high-dimensional classical and quantum information commu...Recognized in the 1990s,vortex beams'ability to carry orbital angular momentum(OAM)has significantly contributed to applications in optical manipulation and high-dimensional classical and quantum information communication.However,inherent diffraction in free space results in the inevitable expansion of beam size and divergence contingent upon the OAM,limiting vortex beams'applicability in areas such as spatial mode multiplexing communication,fiber-optic data transmission,and particle manipulation.These domains necessitate vortex beams with OAM-independent propagation characteristics.We introduce iso-propagation vortices(IPVs),vortex beams characterized by OAM-independent propagation behavior,achieved through precise radial index configuration of Laguerre-Gaussian beams.IPVs display notable transmission dynamics,including a reduced quality factor,resilience post-damage,and decreased and uniform modal scattering under atmospheric turbulence.Their distinctive attributes render IPVs valuable for potential applications in imaging,microscopy,optical communication,metrology,quantum information processing,and light-matter interactions.Notably,within optical communication,the case study suggests that the IPV basis,due to its OAM-independent propagation behavior,provides access to a more extensive spectrum of data channels compared with conventional spatial multiplexing techniques,consequently augmenting information capacity.展开更多
Considerable attention has been recently paid to elucidation the linear,nonlinear and quantum physics of moire patterns because of the innate extraordinary physical properties and potential applications.Particularly,m...Considerable attention has been recently paid to elucidation the linear,nonlinear and quantum physics of moire patterns because of the innate extraordinary physical properties and potential applications.Particularly,moire superlattices consisted of two periodic structures with a twist angle offer a new platform for studying soliton theory and its practical applications in various physical systems including optics,while such studies were so far limited to reversible or conservative nonlinear systems.Herein,we provide insight into soliton physics in dissipative physical settings with moire optical lattices,using numerical simulations and theoretical analysis.We reveal linear localization-delocalization transitions,and find that such nonlinear settings support plentiful localized gap modes representing as dissipative gap solitons and vortices in periodic and aperiodic moire optical lattices,and identify numerically the stable regions of these localized modes.Our predicted dissipative localized modes provide insightful understanding of soliton physics in dissipative nonlinear systems since dissipation is everywhere.展开更多
Spatiotemporal optical vortex(STOV)wavepacket carrying transverse photonic orbital angular momentum(OAM)has been extensively studied in the past few years.In this Letter,we propose and study a novel STOV wavepacket wi...Spatiotemporal optical vortex(STOV)wavepacket carrying transverse photonic orbital angular momentum(OAM)has been extensively studied in the past few years.In this Letter,we propose and study a novel STOV wavepacket with multiple phase singularities embedded in different space–time domains using analytical and numerical approaches.By tuning different parameters used for designing the wavepacket,it is possible to engineer both the magnitude and orientation of the photonic OAM in space–time.The vectorially controllable OAM will pave new avenues and facilitate applications such as novel optical communication,studying complicated quantum systems,and spin-and-OAM interactions.展开更多
基金National Basic Research Program of China(973Program)(2014CB340004)National Natural Science Foundation of China(NSFC)(11274131,11574001,61222502)+4 种基金National Program for Support of Top-Notch Young ProfessionalsProgram for New Century Excellent Talents in University(NCET)(NCET-11-0182)Wuhan Science and Technology Plan Project(2014070404010201)Open Program from State Key Laboratory of Advanced Optical Communication Systems and Networks(2016GZKF0JT007)Open Projects Foundation of Yangtze Optical Fiber and Cable Joint Stock Limited Company(YOFC)(SKLD1504)
文摘An optical vortex having an isolated point singularity is associated with the spatial structure of light waves.A polarization vortex(vector beam) with a polarization singularity has spatially variant polarizations. A phase vortex with phase singularity or screw dislocation has a spiral phase front. The optical vortex has recently gained increasing interest in optical trapping, optical tweezers, laser machining, microscopy, quantum information processing, and optical communications. In this paper, we review recent advances in optical communications using optical vortices. First, basic concepts of polarization/phase vortex modulation and multiplexing in communications and key techniques of polarization/phase vortex generation and(de)multiplexing are introduced. Second, free-space and fiber optical communications using optical vortex modulation and optical vortex multiplexing are presented. Finally, key challenges and perspectives of optical communications using optical vortices are discussed. It is expected that optical vortices exploiting the space physical dimension of light waves might find more interesting applications in optical communications and interconnects.
基金LC thanks Jonathan Leach for previous illuminating discussions about the OAM spreading effect and the National Natural Science Foundation of China(Grant No.11104233)the Fundamental Research Funds for the Central Universities(Grants Nos.2011121043,2012121015)+1 种基金the Natural Science Foundation of Fujian Province of China(2011J05010)and the Program for New Century Excellent Talents in University of China(Grant No.NCET-13-0495).JR thanks Hamamatsu and Miles Padgett for their kind support of this work.
文摘We demonstrate that the combination of digital spiral imaging with high-dimensional orbital angular momentum(OAM)entanglement can be used for efficiently probing and identifying pure phase objects,where the probing light does not necessarily touch the object,via the experimental,non-local decomposition of non-integer pure phase vortices in OAM-entangled photon pairs.The entangled photons are generated by parametric downconversion and then measured with spatial light modulators and single-mode fibers.The fractional phase vortices are defined in the idler photons,while their corresponding spiral spectra are obtained non-locally by scanning the measured OAM states in the signal photons.We conceptually illustrate our results with the biphoton Klyshko picture and the effective dimensionality to demonstrate the high-dimensional nature of the associated quantum OAM channels.Our result is a proof of concept that quantum imaging techniques exploiting high-dimensional entanglement can potentially be used for remote sensing.
基金the National Natural Science Foundation of China(NSFC)(Grant Nos.11574001,61761130082,11774116 and 11274131)the National Basic Research Program of China(973 Program)(No.2014CB340004)+4 种基金the Royal Society-Newton Advanced Fellowshipthe National Program for Support of Top-notch Young Professionalsthe Yangtze River Excellent Young Scholars Programthe Natural Science Foundation of Hubei Province of China(No.2018CFA048)the Program for HUST Academic Frontier Youth Team(No.2016QYTD05).
文摘Optical vortices carrying orbital angular momentum(OAM)have attracted increasing interest in recent years.Optical vortices have seen a variety of emerging applications in optical manipulation,optical trapping,optical tweezers,optical vortex knots,imaging,microscopy,sensing,metrology,quantum information processing,and optical communications.In various optical vortices enabled applications,the generation of multiple optical vortices is of great importance.In this review article,we focus on the methods of multiple optical vortices generation and its applications.We review the methods for generating multiple optical vortices in three cases,i.e.,1-to-N collinear OAM modes,1-to-N OAM mode array and N-to-N collinear OAM modes.Diverse applications of multiple OAM modes in optical communications and non-communication areas are presented.Future trends,perspectives and opportunities are also discussed.
基金National Natural Science Foundation of China(NSFC)(11474238,11734011,91636109)Fundamental Research Funds for the Central Universities at Xiamen University(20720160040)+2 种基金Natural Science Foundation of Fujian Province(2015J06002)Program for New Century Excellent Talents in University(NCET)(NCET-13-0495)National Key R&D Program of China(2017YFA0303700)
文摘The generation and manipulation of optical vortices are of fundamental importance in a variety of promising applications. Here, we develop a nonlinear optical paradigm to implement self- and cross-convolution of optical vortex arrays, demonstrating the features of a vortex copier and regenerator. We use a phase-only spatial light modulator to prepare the 1064 nm invisible fundamental light to carry special optical vortex arrays and use a potassium titanyl phosphate crystal to perform type Ⅱ second-harmonic generation in the Fourier domain to achieve 532 nm visible structured vortices. Based on pure cross-convolution, we succeed in copying arbitrary-order single vortices as well as their superposition states onto a prearranged array of fundamental Gaussian spots. Also, based on the simultaneous effect of self- and cross-convolutions, we can expand the initial vortex lattices to regenerate more vortices carrying various higher topological charges. Our presented method of realizing imaging, an optical vortex copier and regenerator could find direct applications in optical mani optical communication, and quantum information processing with structured vortex pulation, optical arrays.
文摘Non-spreading nature of Bessel spatiotemporal wavepackets is theoretically and experimentally investigated and orders of magnitude improvement in the spatiotemporal spreading has been demonstrated.The spatiotemporal confinement provided by the Bessel spatiotemporal wavepacket is further exploited to transport transverse orbital angular momentum through embedding spatiotemporal optical vortex into the Bessel spatiotemporal wavepacket, constructing a new type of wavepacket: Bessel spatiotemporal optical vortex. Both numerical and experimental results demonstrate that spatiotemporal vortex structure can be well maintained and confined through much longer propagation. High order spatiotemporal optical vortices can also be better confined in the spatiotemporal domain and prevented from further breaking up, overcoming a potential major obstacle for future applications of spatiotemporal vortex.
基金Project supported by the National Natural Science Foundation of China (Grant Nos 10674038 and 10604042)National Basic Research Program of China (Grant No 2006CB302901)+1 种基金the Multidiscipline Scientific Research Foundation of Harbin Institute of Technology, China (Grant No HIT.MD2003.22)the Foundation of Harbin Institute of Technology at Weihai of China (Grant No HIT(WH).2005.20)
文摘This paper introduces a novel method to realize the superposition of orbital angular momentum of photons by combined computer-generated hologram （CCGH） fabricated in silica glass with femtosecond laser pulses. Firstly, the two computer-generated holograms （CGH） of optical vortex were obtained and combined as a CCGH according to the design. Then the CCGH was directly written inside glass by femtosecond laser pulses induced microexplosion without any preor post-treatment of the material. The vortex beams with different vortex topological charges （including new topological charges） have been restructured using a collimated He-Ne laser beam incidence to the CCGH normally. A theoretical and experimental explanation has been presented for the generations of the new topological charges.
基金We acknowledge support from the National Natural Science Foundation of China(NSFC)[Grant Nos.92050202(Q.Z.)and 12104309(Q.C.)]the Shanghai Science and Technology Committee[Grant No.19060502500(Q.Z.)],the Shanghai Sailing Program[Grant No.21YF1431500(Q.C.)]the National Research Foundation of Korea(NRF)funded by the Korea government(MSIT)[Grant No.2022R1A2C1091890(A.C.)].
文摘Spatiotemporal optical vortex(STOV)pulses can carry transverse orbital angular momentum(OAM)that is perpendicular to the direction of pulse propagation.For a STOV pulse,its spatiotemporal profile can be significantly distorted due to unbalanced dispersive and diffractive phases.This may limit its use in many research applications,where a long interaction length and a tight confinement of the pulse are needed.The first demonstration of STOV pulse propagation through a few-mode optical fiber is presented.Both numerical and experimental analysis on the propagation of STOV pulse through a commercially available SMF-28 standard telecommunication fiber is performed.The spatiotemporal phase feature of the pulse can be well kept after the pulse propagates a few-meter length through the fiber even with bending.Further propagation of the pulse will result in a breakup of its spatiotemporal spiral phase structure due to an excessive amount of modal group delay dispersion.The stable and robust transmission of transverse photonic OAM through optical fiber may open new opportunities for transverse photonic OAM studies in telecommunications,OAM lasers,and nonlinear fiber-optical research.
基金supported by the National Natural Science Foundation of China(Grant Nos.12264049 and 11664041)the Xinjiang Normal University Young Outstanding Talent Programme(Grant No.XJNUQB2022-17).
文摘High-order Laguerre–Gaussian(LG)petal-like beams have become a topic of significant interest due to their potential application in next-generation optical trapping,quantum optics,and materials processing technologies.In this work,we demonstrate the generation of high-order LG beams with petal-like spatial profiles and tunable orbital angular momentum(OAM)in the mid-infrared wavelength region.These beams are generated using idler-resonant optical parametric oscillation(OPO)in a KTiOAsO_(4)(KTA)crystal.By adjusting the length of the resonant cavity,the OAM of the mid-infrared idler field can be tuned and we demonstrate tuning in the range of 0 to10.When using a maximum pump energy of 20.2 mJ,the maximum output energy of high-order modes LG_(0.45),LG_(0.48),and LG_(0.410) were 0.8,0.53,and 0.46 mJ,respectively.The means by which high-order LG modes with petal-like spatial profiles and tunable OAM were generated from the OPO is theoretically modeled by examining the spatial overlap efficiency of the beam waists of the pump and resonant idler fields within the center of the KTA crystal.The methodology presented in this work offers a simple and flexible method to wavelength-convert laser emission and generate high-order LG modes.
基金financially supported by the National Key Research and Development Program of China(Grant Nos.2023YFA1406903 and 2022YFA1404800)the National Natural Science Foundation of China(Grant Nos.12374307,12234009,and 12274215)
文摘Recognized in the 1990s,vortex beams'ability to carry orbital angular momentum(OAM)has significantly contributed to applications in optical manipulation and high-dimensional classical and quantum information communication.However,inherent diffraction in free space results in the inevitable expansion of beam size and divergence contingent upon the OAM,limiting vortex beams'applicability in areas such as spatial mode multiplexing communication,fiber-optic data transmission,and particle manipulation.These domains necessitate vortex beams with OAM-independent propagation characteristics.We introduce iso-propagation vortices(IPVs),vortex beams characterized by OAM-independent propagation behavior,achieved through precise radial index configuration of Laguerre-Gaussian beams.IPVs display notable transmission dynamics,including a reduced quality factor,resilience post-damage,and decreased and uniform modal scattering under atmospheric turbulence.Their distinctive attributes render IPVs valuable for potential applications in imaging,microscopy,optical communication,metrology,quantum information processing,and light-matter interactions.Notably,within optical communication,the case study suggests that the IPV basis,due to its OAM-independent propagation behavior,provides access to a more extensive spectrum of data channels compared with conventional spatial multiplexing techniques,consequently augmenting information capacity.
基金supported by the National Natural Science Foundation of China(NSFC)(12074423,11925108,12301306)the Young Scholar of Chinese Academy of Sciences in western China(XAB2021YN18)+1 种基金the Provisional Science Fund for Distinguished Young Scholars of Shaanxi(2024JC-JCQN-11)the Beijing Natural Science Foundation(1234039).
文摘Considerable attention has been recently paid to elucidation the linear,nonlinear and quantum physics of moire patterns because of the innate extraordinary physical properties and potential applications.Particularly,moire superlattices consisted of two periodic structures with a twist angle offer a new platform for studying soliton theory and its practical applications in various physical systems including optics,while such studies were so far limited to reversible or conservative nonlinear systems.Herein,we provide insight into soliton physics in dissipative physical settings with moire optical lattices,using numerical simulations and theoretical analysis.We reveal linear localization-delocalization transitions,and find that such nonlinear settings support plentiful localized gap modes representing as dissipative gap solitons and vortices in periodic and aperiodic moire optical lattices,and identify numerically the stable regions of these localized modes.Our predicted dissipative localized modes provide insightful understanding of soliton physics in dissipative nonlinear systems since dissipation is everywhere.
基金supported by the National Natural Science Foundation of China(NSFC)(Nos.92050202,12104309,and 62005168)the Shanghai Science and Technology Committee(No.19060502500)the Shanghai Sailing Program(No.21YF1431500).
文摘Spatiotemporal optical vortex(STOV)wavepacket carrying transverse photonic orbital angular momentum(OAM)has been extensively studied in the past few years.In this Letter,we propose and study a novel STOV wavepacket with multiple phase singularities embedded in different space–time domains using analytical and numerical approaches.By tuning different parameters used for designing the wavepacket,it is possible to engineer both the magnitude and orientation of the photonic OAM in space–time.The vectorially controllable OAM will pave new avenues and facilitate applications such as novel optical communication,studying complicated quantum systems,and spin-and-OAM interactions.
