Optical orbital angular momentum(OAM)mode multiplexing has emerged as a promising technique for boosting communication capacity.However,most existing studies have concentrated on channel(de)-multiplexing,overlooking t...Optical orbital angular momentum(OAM)mode multiplexing has emerged as a promising technique for boosting communication capacity.However,most existing studies have concentrated on channel(de)-multiplexing,overlooking the critical aspect of channel routing.This challenge involves the reallocation of multiplexed OAM modes across both spatial and temporal domains—a vital step for developing versatile communication networks.To address this gap,we introduce a novel approach based on the time evolution of OAM modes,utilizing the orthogonal conversion and diffractive modulation capabilities of unitary transformations.This approach facilitates high-dimensional orthogonal transformations of OAM mode vectors,altering both the propagation direction and the spatial location.Using Fresnel diffraction matrices as unitary operators,it manipulates the spatial locations of light beams during transmission,breaking the propagation invariance and enabling temporal evolution.As a demonstration,we have experimentally implemented the deep routing of four OAM modes within two distinct time sequences.Achieving an average diffraction efficiency above 78.31%,we have successfully deep-routed 4.69 Tbit-s^(-1)quadrature phase-shift keying(QPSK)signals carried by four multiplexed OAM channels,with a bit error rate below 10^(-6).These results underscore the efficacy of our routing strategy and its promising prospects for practical applications.展开更多
The emergence of cascaded metasurface holography has opened up a promising avenue for realizing high-capacity optical data storage and security information encryption.However,in the majority of existing cascaded confi...The emergence of cascaded metasurface holography has opened up a promising avenue for realizing high-capacity optical data storage and security information encryption.However,in the majority of existing cascaded configurations,the inherent cascade-phase overlap prevents the retrieval of additional holographic information from each single-layer metasurface unless these metasurfaces are physically separated.To overcome this limitation,we propose a controllable cascade-phase modulation solution for enabling flexible switching between single-layer and cascaded holograms that utilizes helicitydecoupled Ge_(2)Sb_(2)Te_(5)(GST)metasurfaces.By harnessing the prominent optical-phase response contrast in GST transition,we show that phase-type holographic profiles tailored using GST nanopillars can be arbitrarily retrieved in their amorphous state while completely hidden in the crystalline state;this allows the active separation and combination of bilayer phases through controlling the amorphous-crystalline state transition of GST.Additionally,combined with the helicity-decoupled phase modulation mechanism,the optical dual-helicity channels offer polarization control operation for cascade-phase function switching.As a proof-of-concept,the designed GST metasurfaces are used to successfully reconstruct four single-layer and two cascaded holographic images separately through a synergistic control of the GST transition and by leveraging the helicity of the incident light.This feature also results in a reliable holographic encryption strategy for transmitting ciphered information.The proposed technology not only overcomes the physical constraints of multilayer phase overlap but is also compatible with existing cascade-related holographic multiplexing methodologies,which may promote the advanced explorations of optical multilevel modulation,multidimensional displays,and high-density optical storage.展开更多
Optical vortices,characterized by their infinite orthogonal eigenmodes—such as orbital angular momentum(OAM)and cylindrical vector beam(CVB)modes—offer unprecedented opportunities for advancing optical communication...Optical vortices,characterized by their infinite orthogonal eigenmodes—such as orbital angular momentum(OAM)and cylindrical vector beam(CVB)modes—offer unprecedented opportunities for advancing optical communication systems.The core components of these systems—mode(de)modulation,mode processing,and mode transmission—are fundamental to the construction and networking of OAM/CVB mode-based communication networks.They significantly influence signal encoding,enhance channel capacity,and facilitate signal interconnection and transmission.We explore the historical development and recent advancements in optical vortex-based communication systems from these three critical perspectives.We systematically summarize the normative definitions and research progress related to key concepts such as mode multiplexing and routing.We also demonstrate the performance of these systems in terms of communication capacity,bit error rate,and more.Furthermore,we examine the substantial challenges and future prospects in this field,with the aim of offering cutting-edge insights that will facilitate the advancement and practical implementation of optical communication networks leveraging optical vortex modes.展开更多
Orbital angular momentum(OAM)modes provide an additional orthogonal physical dimension,offering transformative potential for enhancing optical communication capacity.Despite significant progress in mode multiplexing,t...Orbital angular momentum(OAM)modes provide an additional orthogonal physical dimension,offering transformative potential for enhancing optical communication capacity.Despite significant progress in mode multiplexing,the development of robust communication networks faces persistent challenges,particularly in effectively routing and controlling these multiplexed channels among network nodes.To tackle these dilemmas,we propose a rotatable diffractive neural network(R-DNN)strategy and demonstrate its capability for port-controllable OAM mode routing.By leveraging the correlation between the orthogonal evolution of OAM modes in free space and phase modulations during propagation,the R-DNN precisely shapes the spatial evolution of mode fields through multiple rotatable phase layers,enabling efficient routing to specific output ports.This approach exploits the interaction of secondary wavelets with the relative states of the rotatable layers,allowing on-demand control of mode evolution paths and enhancing routing flexibility.As a proof of concept,we developed a tri-functional router that successfully directs three OAM modes to individually controllable output ports.This router achieves an average intermode crosstalk of less than−16.4 dB across three functional states,one-dimensional,two-dimensional,and cross-connected switching,while supporting the routing of 5.85 Tbit/s quadrature phase-shift keying signals.These results highlight the R-DNN’s effectiveness in achieving precise and controllable OAM mode manipulation,paving the way for advanced applications in mode-multiplexed communication networks and beyond.展开更多
Tongren Dahuoluo Wan has been a popular traditional Chinese medicine in international pharmaceutical markets for hundreds of years. Leopard bone powder is the key element in its formulation. However, the leopard has b...Tongren Dahuoluo Wan has been a popular traditional Chinese medicine in international pharmaceutical markets for hundreds of years. Leopard bone powder is the key element in its formulation. However, the leopard has been listed for wildlife conservation, which limits the use of the leopard bone supplies. Therefore, an alternative formulation which substitutes leopard bone with zokor bone in the formula of Tongren Dahuoluo Wan is now manufactured. To develop a simple and reliable molecular method for authenticating the two patent medicines,mitochondrial nucleotide polymorphic sites of 12 S rRNA,COI and Cytb genes were screened in leopard and zokor bones, and nine pairs of species-specific primers were verified for discriminating the two species. For the patent medicine authentication, we set up a molecular diagnostic assay to resolve the difficulties of low concentration of target DNAs and presence of PCR-inhibitory substances in this complex medicine, and successfully confirmed leopard or zokor content using the nine pairs of species-specific primers. We recommend a common technical strategy for authentication of species origins in traditional Chinese medicine, and discuss the experimental solutions for technical problems of molecular diagnostic assays.展开更多
基金the National Natural Science Foundation of China(62271322)the Guangdong Basic and Applied Basic Research Foundation(2022A1515011003 and 2023A1515030152)the Shenzhen Science and Technology Program(JCYJ20210324095610027 and JCYJ20210324095611030).
文摘Optical orbital angular momentum(OAM)mode multiplexing has emerged as a promising technique for boosting communication capacity.However,most existing studies have concentrated on channel(de)-multiplexing,overlooking the critical aspect of channel routing.This challenge involves the reallocation of multiplexed OAM modes across both spatial and temporal domains—a vital step for developing versatile communication networks.To address this gap,we introduce a novel approach based on the time evolution of OAM modes,utilizing the orthogonal conversion and diffractive modulation capabilities of unitary transformations.This approach facilitates high-dimensional orthogonal transformations of OAM mode vectors,altering both the propagation direction and the spatial location.Using Fresnel diffraction matrices as unitary operators,it manipulates the spatial locations of light beams during transmission,breaking the propagation invariance and enabling temporal evolution.As a demonstration,we have experimentally implemented the deep routing of four OAM modes within two distinct time sequences.Achieving an average diffraction efficiency above 78.31%,we have successfully deep-routed 4.69 Tbit-s^(-1)quadrature phase-shift keying(QPSK)signals carried by four multiplexed OAM channels,with a bit error rate below 10^(-6).These results underscore the efficacy of our routing strategy and its promising prospects for practical applications.
基金supported by the National Natural Science Foundation of China(Grant No.62271322)the Guangdong Basic and Applied Basic Research Foundation(Grant No.2023A1515030152)+2 种基金the Science and Technology Project of Shenzhen(Grant No.ZDSYS201707271014468)the Shenzhen Science and Technology Program(Grant No.JCYJ20240813143018024)the Natural Science Foundation of Top Talent of SZTU(Grant No.GDRC202204)。
文摘The emergence of cascaded metasurface holography has opened up a promising avenue for realizing high-capacity optical data storage and security information encryption.However,in the majority of existing cascaded configurations,the inherent cascade-phase overlap prevents the retrieval of additional holographic information from each single-layer metasurface unless these metasurfaces are physically separated.To overcome this limitation,we propose a controllable cascade-phase modulation solution for enabling flexible switching between single-layer and cascaded holograms that utilizes helicitydecoupled Ge_(2)Sb_(2)Te_(5)(GST)metasurfaces.By harnessing the prominent optical-phase response contrast in GST transition,we show that phase-type holographic profiles tailored using GST nanopillars can be arbitrarily retrieved in their amorphous state while completely hidden in the crystalline state;this allows the active separation and combination of bilayer phases through controlling the amorphous-crystalline state transition of GST.Additionally,combined with the helicity-decoupled phase modulation mechanism,the optical dual-helicity channels offer polarization control operation for cascade-phase function switching.As a proof-of-concept,the designed GST metasurfaces are used to successfully reconstruct four single-layer and two cascaded holographic images separately through a synergistic control of the GST transition and by leveraging the helicity of the incident light.This feature also results in a reliable holographic encryption strategy for transmitting ciphered information.The proposed technology not only overcomes the physical constraints of multilayer phase overlap but is also compatible with existing cascade-related holographic multiplexing methodologies,which may promote the advanced explorations of optical multilevel modulation,multidimensional displays,and high-density optical storage.
基金supported by the National Natural Science Foundation of China(Grant Nos.62271322,61935013,62375181,62335019,62475294,and 62475290)the Guangdong Major Project of Basic Research(Grant No.2020B0301030009)+5 种基金the Basic and Applied Basic Research Foundation of Guangdong(Grant Nos.2023A1515030152 and 2021B1515020093)the Shenzhen Peacock Plan(Grant No.KQTD20170330110444030)the Scientific Instrument Developing Project of Shenzhen University(Grant No.2023YQ001)the Shenzhen University 2035 Initiative(Grant No.2023B004)the Natural Science Foundation of Top Talent of SZTU(Grant No.GDRC202204)the Fundamental Research Funds for the Central Universities,Sun Yat-sen University(Grant No.24xkjc015)。
文摘Optical vortices,characterized by their infinite orthogonal eigenmodes—such as orbital angular momentum(OAM)and cylindrical vector beam(CVB)modes—offer unprecedented opportunities for advancing optical communication systems.The core components of these systems—mode(de)modulation,mode processing,and mode transmission—are fundamental to the construction and networking of OAM/CVB mode-based communication networks.They significantly influence signal encoding,enhance channel capacity,and facilitate signal interconnection and transmission.We explore the historical development and recent advancements in optical vortex-based communication systems from these three critical perspectives.We systematically summarize the normative definitions and research progress related to key concepts such as mode multiplexing and routing.We also demonstrate the performance of these systems in terms of communication capacity,bit error rate,and more.Furthermore,we examine the substantial challenges and future prospects in this field,with the aim of offering cutting-edge insights that will facilitate the advancement and practical implementation of optical communication networks leveraging optical vortex modes.
基金supported by the National Natural Science Foundation of China(Grant Nos.62271322,62331004,and 62222501)the Guangdong Basic and Applied Basic Research Foundation(Grant No.2023A1515030152)+1 种基金the Science and Technology Project of Shenzhen(Grant No.ZDSYS201707271014468)the Natural Science Foundation of Top Talent of SZTU(Grant No.GDRC202204)。
文摘Orbital angular momentum(OAM)modes provide an additional orthogonal physical dimension,offering transformative potential for enhancing optical communication capacity.Despite significant progress in mode multiplexing,the development of robust communication networks faces persistent challenges,particularly in effectively routing and controlling these multiplexed channels among network nodes.To tackle these dilemmas,we propose a rotatable diffractive neural network(R-DNN)strategy and demonstrate its capability for port-controllable OAM mode routing.By leveraging the correlation between the orthogonal evolution of OAM modes in free space and phase modulations during propagation,the R-DNN precisely shapes the spatial evolution of mode fields through multiple rotatable phase layers,enabling efficient routing to specific output ports.This approach exploits the interaction of secondary wavelets with the relative states of the rotatable layers,allowing on-demand control of mode evolution paths and enhancing routing flexibility.As a proof of concept,we developed a tri-functional router that successfully directs three OAM modes to individually controllable output ports.This router achieves an average intermode crosstalk of less than−16.4 dB across three functional states,one-dimensional,two-dimensional,and cross-connected switching,while supporting the routing of 5.85 Tbit/s quadrature phase-shift keying signals.These results highlight the R-DNN’s effectiveness in achieving precise and controllable OAM mode manipulation,paving the way for advanced applications in mode-multiplexed communication networks and beyond.
基金supported by projects of Beijing Municipal Science & Technology Commission (D08080203640903)National Natural Science Foundation of China (31672379)
文摘Tongren Dahuoluo Wan has been a popular traditional Chinese medicine in international pharmaceutical markets for hundreds of years. Leopard bone powder is the key element in its formulation. However, the leopard has been listed for wildlife conservation, which limits the use of the leopard bone supplies. Therefore, an alternative formulation which substitutes leopard bone with zokor bone in the formula of Tongren Dahuoluo Wan is now manufactured. To develop a simple and reliable molecular method for authenticating the two patent medicines,mitochondrial nucleotide polymorphic sites of 12 S rRNA,COI and Cytb genes were screened in leopard and zokor bones, and nine pairs of species-specific primers were verified for discriminating the two species. For the patent medicine authentication, we set up a molecular diagnostic assay to resolve the difficulties of low concentration of target DNAs and presence of PCR-inhibitory substances in this complex medicine, and successfully confirmed leopard or zokor content using the nine pairs of species-specific primers. We recommend a common technical strategy for authentication of species origins in traditional Chinese medicine, and discuss the experimental solutions for technical problems of molecular diagnostic assays.
