In this paper,we propose a new protocol designed for quantum private comparison(QPC).This new protocol utilizes the hyperentanglement as the quantum resource and introduces a semi-honest third party(TP)to achieve the ...In this paper,we propose a new protocol designed for quantum private comparison(QPC).This new protocol utilizes the hyperentanglement as the quantum resource and introduces a semi-honest third party(TP)to achieve the objective.This protocol’s quantum carrier is a hyperentangled three-photon GHZ state in 2 degrees of freedom(DOF),which could have 64 combinations.The TP can decide which combination to use based on the shared key information provided from a quantum key distribution(QKD)protocol.By doing so,the security of the protocol can be improved further.Decoy photon technology is also used as another means of security and checks if the transmission in the quantum channel is secure or not before sending the quantum carrier.The proposed protocol is proved to be able to fend off various kinds of eavesdropping attacks.In addition,the new QPC protocol also can compare secret inputs securely and efficiently.展开更多
We propose a scheme for generating a hyperentangled four-photon cluster state that is simultaneously entangled in polarization modes and spatial modes. This scheme is based on linear optical elements, weak cross-Kerr ...We propose a scheme for generating a hyperentangled four-photon cluster state that is simultaneously entangled in polarization modes and spatial modes. This scheme is based on linear optical elements, weak cross-Kerr nonlinearity, and homodyne detection. Therefore, it is feasible with current experimental technology.展开更多
We present an efficient scheme for the complete analysis of hyperentangled Greenberger–Horne–Zeilinger(GHZ)state in polarization and time-bin degrees of freedom with two steps. Firstly, the polarization GHZ state is...We present an efficient scheme for the complete analysis of hyperentangled Greenberger–Horne–Zeilinger(GHZ)state in polarization and time-bin degrees of freedom with two steps. Firstly, the polarization GHZ state is distinguished completely and nondestructively, resorting to the controlled phase flip(CPF) gate constructed by the cavity-assisted interaction. Subsequently, the time-bin GHZ state is analyzed by using the preserved polarization entanglement. With the help of CPF gate and self-assisted mechanism, our scheme can be directly generalized to the complete N-photon hyperentangled GHZ state analysis, and it may have potential applications in the hyperentanglement-based quantum communication.展开更多
We propose the schemes for implementing hyperentangled state analysis and generating four-electron high entan-gled states （including cluster state, ｜X） state, and symmetric Dicke state） based on the charge detecti...We propose the schemes for implementing hyperentangled state analysis and generating four-electron high entan-gled states （including cluster state, ｜X） state, and symmetric Dicke state） based on the charge detection of free electrons. These schemes are deterministic and rely only on charge detection and single-spin rotations. This method, which uses noninteracting electrons, is not only efficient but also saves on quantum resources.展开更多
Hyperentanglement is a promising resource for achieving high capacity quantum communication.Here,we propose a compact scheme for the generation of path-frequency hyperentangled photon pairs via spontaneous parametric ...Hyperentanglement is a promising resource for achieving high capacity quantum communication.Here,we propose a compact scheme for the generation of path-frequency hyperentangled photon pairs via spontaneous parametric down-conversion(SPDC)processes,where six different paths and two different frequencies are covered.A two-dimensional periodicalχ^((2))nonlinear photonic crystal(NPC)is designed to satisfy type-Ⅰquasi-phase-matching conditions in the plane perpendicular to the incident pump beam,and a perfect phase match is achieved along the pump beam's direction to ensure high conversion efficiency,with theoretically estimated photon flux up to 2.068×10^(5) pairs·s^(-1)·mm^(-2).We theoretically calculate the joint-spectral amplitude(JSA)of the generated photon pair and perform Schmidt decomposition on it,where the resulting entropy S of entanglement and effective Schmidt rank K reach 3.2789 and 6.4675,respectively.Our hyperentangled photon source scheme could provide new avenues for high-dimensional quantum communication and high-speed quantum information processing.展开更多
Generation of hyperentangled photon pairs is investigated based on the lithium niobate straight waveguide.We propose to use the nonlinear optical process of spontaneous parametric down-conversion(SPDC)and a well-desig...Generation of hyperentangled photon pairs is investigated based on the lithium niobate straight waveguide.We propose to use the nonlinear optical process of spontaneous parametric down-conversion(SPDC)and a well-designed lithium niobate waveguide structure to generate a hyperentangled(in the polarization dimension and the energy-time dimension)two-photon state.By performing numerical simulations of the waveguide structure and calculating the possible polarization states,joint spectral amplitudes(JSA),and joint temporal amplitudes(JTA)of the generated photon pair,we show that the generated photon pair is indeed hyperentangled in both the polarization dimension and the energy-time dimension.展开更多
In this paper,we present a novel method for the complete analysis of maximally hyperentangled state of photon system in two degrees of freedom(DOFs),resorting to the auxiliary high-dimensional entanglement in the thir...In this paper,we present a novel method for the complete analysis of maximally hyperentangled state of photon system in two degrees of freedom(DOFs),resorting to the auxiliary high-dimensional entanglement in the third DOF.This method not only can be used for complete hyperentangled Bell state analysis of two-photon system,but also can be suitable for complete hyperentangled Greenberger-Horne-Zeilinger(GHZ)state analysis of three-photon system,and can be extended to the complete Nphoton hyperentangled GHZ state analysis.In our approach,the parity information of hyperentanglement is determined via the measurement on evolved auxiliary high-dimensional entanglement,and the relative phase information of hyperentanglement is determined via the projective measurement.Moreover,this approach can be accomplished by just using linear optics,and is significant for the investigation of photonic hyperentangled state analysis.展开更多
Hyperentangled Bell states analysis(HBSA)is an essential building block for certain hyper-parallel quantum information processing.We propose a complete and deterministic HBSA scheme encoded in spatial and polarization...Hyperentangled Bell states analysis(HBSA)is an essential building block for certain hyper-parallel quantum information processing.We propose a complete and deterministic HBSA scheme encoded in spatial and polarization degrees of freedom(DOFs)of two-photon system assisted by a fixed frequency-based entanglement and a time interval DOF.The parity information the spatial-based and polarization-based hyper-entanglement can be distinguished by the distinct time intervals of the photon pairs,and the phase information can be distinguished by the detection signature.Compared with previous schemes,the number of the auxiliary entanglements is reduced from two to one by introducing time interval DOF.Moreover,the additional frequency and time interval DOFs suffer less from the collective channel noise.展开更多
Exploiting the fantastic features of quantum mechanics,a hyperentangled quantum network encoded in multiple degree of freedoms(DOF),e.g.,polarization and orbital angular momentum DOFs,can encode more qubits per transm...Exploiting the fantastic features of quantum mechanics,a hyperentangled quantum network encoded in multiple degree of freedoms(DOF),e.g.,polarization and orbital angular momentum DOFs,can encode more qubits per transmitted photon and offers a promising platform for many dramatic applications.Here,we demonstrate such a hyperentangled multiuser network with a fully connected network architecture by using dense wavelength division multiplexing and entanglement transfer technique.Three hyperentangled states in polarization and time-energy DOFs are multiplexed to three single mode fibers to form the fully connected network architecture.Then,three interferometric quantum gates are utilized for transferring quantum entanglement from time-energy to orbital angular momentum DOF.The experimental results reveal a high quality of the hyperentanglement of the constructed network with the entangled state fidelity of higher than 96%.Our approach can provide a novel way to construct a large-scale hyperentangled network that can support various kinds of quantum tasks like superdense coding and teleportation.展开更多
Hyperentangled-Bell-state analysis(HBSA) is critical for high-capacity quantum communication. Based on a recent proposal by Wang et al. [Opt. Express 24, 28444(2016)], we design two independent schemes for error-heral...Hyperentangled-Bell-state analysis(HBSA) is critical for high-capacity quantum communication. Based on a recent proposal by Wang et al. [Opt. Express 24, 28444(2016)], we design two independent schemes for error-heralded deterministic generation and self-assisted complete HBSA of two-photon systems entangled in both polarization and spatial-mode degrees of freedom(DOFs).Unlike previous programs, we firstly propose an error-heralded block with a singly charged quantum dot inside a single-sided optical microcavity, with which errors due to imperfect interactions between photons and quantum dot systems can be heralded.The error-heralded block, ensures that the fidelity of the two schemes for hyperentangled-Bell-state generation and complete HBSA reaches unity. Moreover, hyperentanglement makes it possible to analyze the polarization state with the assistance of the measured spatial-mode state. The self-assisted mechanism of HBSA greatly simplifies the analytical process and significantly relaxes the requirements of nonlinearities. Therefore, these schemes promise to be implemented more easily in experiments,taking a step closer to long-distance high-capacity quantum communication.展开更多
Encoding many qubits in different degrees of freedom(DOFs)of single photons is one of the routes toward enlarging the Hilbert space spanned by a photonic quantum state.Hyperentangled photon states(that is,states showi...Encoding many qubits in different degrees of freedom(DOFs)of single photons is one of the routes toward enlarging the Hilbert space spanned by a photonic quantum state.Hyperentangled photon states(that is,states showing entanglement in multiple DOFs)have demonstrated significant implications for both fundamental physics tests and quantum communication and computation.Increasing the number of qubits of photonic experiments requires miniaturization and integration of the basic elements,and functions to guarantee the setup stability,which motivates the development of technologies allowing the precise control of different photonic DOFs on a chip.We demonstrate the contextual use of path and polarization qubits propagating within an integrated quantum circuit.We tested the properties of four-qubit linear cluster states built on both DOFs,and we exploited them to perform the Grover's search algorithm according to the one-way quantum computation model.Our results pave the way toward the full integration on a chip of hybrid multi-qubit multiphoton states.展开更多
Hyperentanglement, the simultaneous entanglement in more than one degree of freedom(DOF), plays an important role in quantum communication and quantum information processing for it can effectively increase the channel...Hyperentanglement, the simultaneous entanglement in more than one degree of freedom(DOF), plays an important role in quantum communication and quantum information processing for it can effectively increase the channel capacity. Existing hyperentanglement sources mainly focus on the generation of the hyperentanglement in two DOFs. In this paper, we design the generation protocols for three kinds of hyperentanglement encoded in three DOFs with the practical coherent pulses sources, including the polarization-frequency-space hyperentanglement, the polarization-frequency-time-bin hyperentanglement, and the polarizationspace-time-bin hyperentanglement. These protocols exploit the spontaneous parametric down-conversion(SPDC) process and the Sagnac interferometer. The three protocols are all based on feasible experimental condition and may have potential applications in future hyperentanglement-based quantum communication and quantum information processing protocols.展开更多
This study proposes the first high-capacity quantum secure direct communication(QSDC) with two-photon six-qubit hyperentangled Bell states in two longitudinal momentum and polarization degrees of freedom(DOFs) of phot...This study proposes the first high-capacity quantum secure direct communication(QSDC) with two-photon six-qubit hyperentangled Bell states in two longitudinal momentum and polarization degrees of freedom(DOFs) of photon pairs, which can be generated using two 0.5 mm-thick type-I β barium borate crystal slabs aligned one behind the other and an eight-hole screen. The secret message can be independently encoded on the photon pairs with 64 unitary operations in all three DOFs. This protocol has a higher capacity than previous QSDC protocols because each photon pair can carry 6 bits of information, not just 2 or 4 bits.Our QSDC protocol decreases the influence of decoherence from environment noise by exploiting the decoy photons to check the security of the transmission of the first photon sequence. Compared with two-way QSDC protocols, our QSDC protocol is immune to an attack by an eavesdropper using Trojan horse attack strategies because it is a one-way quantum communication.The QSDC protocol has good applications in the future quantum communication because of all these features.展开更多
We present a scheme for quantum superdense coding with hyperentanglement, in which the sender can transfer four bits of classical information by sending only one photon. The important device in the scheme is the hyper...We present a scheme for quantum superdense coding with hyperentanglement, in which the sender can transfer four bits of classical information by sending only one photon. The important device in the scheme is the hyperentangled Bell-state analyzer in both polarization and frequency degrees of freedom, which is also constructed in the paper by using a quantum nondemolition detector assisted by cross-Kerr nonlinearity. Our scheme can transfer more informationwith less resources than the existing schemes and is nearly deterministic and nondestructive.展开更多
We propose a two-step quantum secure direct communication （QSDC） protocol with hyperentanglement in both the spatial-mode and the polarization degrees of freedom of photon pairs which can in principle be produced wi...We propose a two-step quantum secure direct communication （QSDC） protocol with hyperentanglement in both the spatial-mode and the polarization degrees of freedom of photon pairs which can in principle be produced with a beta barium borate crystal. The secret message can be encoded on the photon pairs with unitary operations in these two degrees of freedom independently. This QSDC protocol has a higher capacity than the original two-step QSDC protocol as each photon pair can carry 4 bits of information. Compared with the QSDC protocol based on hyperdense coding, this QSDC protocol has the immunity to Trojan horse attack strategies with the process for determining the number of the photons in each quantum signal as it is a one-way quantum communication protocol.展开更多
We propose two schemes for realizing quantum secure direct communication (QSDC)by using a set ofordered two-photon three-dimensional hyperentangled states entangled in two degrees of freedom (DOFs)as quantuminformatio...We propose two schemes for realizing quantum secure direct communication (QSDC)by using a set ofordered two-photon three-dimensional hyperentangled states entangled in two degrees of freedom (DOFs)as quantuminformation channels.In the first scheme,the photons from Bob to Alice are transmitted only once.After insuring thesecurity of the quantum channels,Bob encodes the secret message on his photons.Then Alice performs single-photontwo-DOF Bell bases measurements on her photons.This scheme has better security than former QSDC protocols.In thesecond scheme,Bob transmits photons to Alice twice.After insuring the security of the quantum channels,Bob encodesthe secret message on his photons.Then Alice performs two-photon Bell bases measurements on each DOF.The schemehas more information capacity than former QSDC protocols.展开更多
We propose a bidirectional quantum secure direct communication(QSDC) network protocol with the hyperentanglment in both the spatial-mode ad the polarization degrees of freedom of photon pairs which can in principle be...We propose a bidirectional quantum secure direct communication(QSDC) network protocol with the hyperentanglment in both the spatial-mode ad the polarization degrees of freedom of photon pairs which can in principle be produced with a beta barium borate crystal.The secret message can be encoded on the photon pairs with unitary operations in these two degrees of freedom independently.Compared with other QSDC network protocols,our QSDC network protocol has a higher capacity as each photon pair can carry 4 bits of information.Also,we discuss the security of our QSDC network protocol and its feasibility with current techniques.展开更多
The one-step quantum secure direct communication(QSDC)(Sci.Bull.67,367(2022))can effectively simplify QSDC’s operation and reduce message loss.For enhancing its security under practical experimental condition,we prop...The one-step quantum secure direct communication(QSDC)(Sci.Bull.67,367(2022))can effectively simplify QSDC’s operation and reduce message loss.For enhancing its security under practical experimental condition,we propose two measurement-device-independent(MDI)one-step QSDC protocols,which can resist all possible attacks from imperfect measurement devices.In both protocols,the communication parties prepare identical polarization-spatial-mode two-photon hyperentangled states and construct the hyperentanglement channel by hyperentanglement swapping.The first MDI one-step QSDC protocol adopts the nonlinear-optical complete hyperentanglement Bell state measurement(HBSM)to construct the hyperentanglement channel,while the second protocol adopts the linear-optical partial HBSM.Then,the parties encode the photons in the polarization degree of freedom and send them to the third party for the hyperentanglementassisted complete polarization Bell state measurement.Both protocols are unconditionally secure in theory.The simulation results show the MDI one-step QSDC protocol with complete HBSM attains the maximal communication distance of about354 km.Our MDI one-step QSDC protocols may have potential applications in the future quantum secure communication field.展开更多
Higher channel capacity and security are difficult to reach in a noisy channel. The loss of photons and the distortion of the qubit state are caused by noise. To solve these problems, in our study, a hyperentangled Be...Higher channel capacity and security are difficult to reach in a noisy channel. The loss of photons and the distortion of the qubit state are caused by noise. To solve these problems, in our study, a hyperentangled Bell state is used to design faithful deterministic secure quantum communication and authentication protocol over collective-rotation and collective-dephasing noisy channel, which doubles the channel capacity compared with using an ordinary Bell state as a carrier; a logical hyperentangled Bell state immune to collective-rotation and collective-dephasing noise is constructed. The secret message is divided into several parts to transmit, however the identity strings of Alice and Bob are reused. Unitary operations are not used.展开更多
We present a deterministic nondestructive hyperentangled Bell state analysis protocol for photons entangled in three degrees of freedom(DOFs),including polarization,spatial-mode,and time-bin DOFs.The polarization Bell...We present a deterministic nondestructive hyperentangled Bell state analysis protocol for photons entangled in three degrees of freedom(DOFs),including polarization,spatial-mode,and time-bin DOFs.The polarization Bell state analyzer and spatial-mode Bell state analyzer are constructed by polarization parity-check quantum nondemolition detector(P-QND)and spatial-mode parity-check quantum nondemolition detector(S-QND)using cross-Kerr nonlinearity,respectively.The time-bin Bell state analyzer is constructed by the swap gate for polarization state and time-bin state of a photon(P-T swap gate)and P-QND.The Bell states analyzer for one DOF will not destruct the Bell states of other two DOFs,so the polarization-spatial-time-bin hyperentangled Bell states can be determinately distinguished without destruction.This deterministic nondestructive state analysis method has useful applications in quantum information protocols.展开更多
文摘In this paper,we propose a new protocol designed for quantum private comparison(QPC).This new protocol utilizes the hyperentanglement as the quantum resource and introduces a semi-honest third party(TP)to achieve the objective.This protocol’s quantum carrier is a hyperentangled three-photon GHZ state in 2 degrees of freedom(DOF),which could have 64 combinations.The TP can decide which combination to use based on the shared key information provided from a quantum key distribution(QKD)protocol.By doing so,the security of the protocol can be improved further.Decoy photon technology is also used as another means of security and checks if the transmission in the quantum channel is secure or not before sending the quantum carrier.The proposed protocol is proved to be able to fend off various kinds of eavesdropping attacks.In addition,the new QPC protocol also can compare secret inputs securely and efficiently.
基金supported by the Major Research Plan of the National Natural Science Foundation of China(Grant No.91121023)the National Natural Science Foundation of China(Grant Nos.60978009 and 61378012)+2 种基金the Specialized Research Fund for the Doctoral Program of Higher Education of China(Grant No.20124407110009)the"973"Project(Grant Nos.2011CBA00200 and 2013CB921804)the PCSIRT(Grant No.IRT1243)
文摘We propose a scheme for generating a hyperentangled four-photon cluster state that is simultaneously entangled in polarization modes and spatial modes. This scheme is based on linear optical elements, weak cross-Kerr nonlinearity, and homodyne detection. Therefore, it is feasible with current experimental technology.
文摘We present an efficient scheme for the complete analysis of hyperentangled Greenberger–Horne–Zeilinger(GHZ)state in polarization and time-bin degrees of freedom with two steps. Firstly, the polarization GHZ state is distinguished completely and nondestructively, resorting to the controlled phase flip(CPF) gate constructed by the cavity-assisted interaction. Subsequently, the time-bin GHZ state is analyzed by using the preserved polarization entanglement. With the help of CPF gate and self-assisted mechanism, our scheme can be directly generalized to the complete N-photon hyperentangled GHZ state analysis, and it may have potential applications in the hyperentanglement-based quantum communication.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11165015,61068001,and 11264042)the Natural Science Foundationof Jilin Province,China(Grant No.201115226)
文摘We propose the schemes for implementing hyperentangled state analysis and generating four-electron high entan-gled states （including cluster state, ｜X） state, and symmetric Dicke state） based on the charge detection of free electrons. These schemes are deterministic and rely only on charge detection and single-spin rotations. This method, which uses noninteracting electrons, is not only efficient but also saves on quantum resources.
基金Project supported by the Key-Area Research and Development Program of Guangdong Province of China (Grant No.2018B030325002)the National Natural Science Foundation of China (Grant No.62075129)+2 种基金the Open Project Program of SJTU-Pinghu Institute of Intelligent Optoelectronics (Grant No.2022SPIOE204)the Science and Technology on Metrology and Calibration Laboratory (Grant No.JLJK2022001B002)the Sichuan Provincial Key Laboratory of Microwave Photonics (Grant No.2023-04)。
文摘Hyperentanglement is a promising resource for achieving high capacity quantum communication.Here,we propose a compact scheme for the generation of path-frequency hyperentangled photon pairs via spontaneous parametric down-conversion(SPDC)processes,where six different paths and two different frequencies are covered.A two-dimensional periodicalχ^((2))nonlinear photonic crystal(NPC)is designed to satisfy type-Ⅰquasi-phase-matching conditions in the plane perpendicular to the incident pump beam,and a perfect phase match is achieved along the pump beam's direction to ensure high conversion efficiency,with theoretically estimated photon flux up to 2.068×10^(5) pairs·s^(-1)·mm^(-2).We theoretically calculate the joint-spectral amplitude(JSA)of the generated photon pair and perform Schmidt decomposition on it,where the resulting entropy S of entanglement and effective Schmidt rank K reach 3.2789 and 6.4675,respectively.Our hyperentangled photon source scheme could provide new avenues for high-dimensional quantum communication and high-speed quantum information processing.
基金the Key-Area Research and Development Program of Guangdong Province of China(Grant No.2018B030325002)the National Natural Science Foundation of China(Grant No.62075129)+1 种基金the Open Project Program of SJTU-Pinghu Institute of Intelligent Optoelectronics(Grant No.2022SPIOE204)the Science and Technology on Metrology and Calibration Laboratory(Grant No.JLJK2022001B002)。
文摘Generation of hyperentangled photon pairs is investigated based on the lithium niobate straight waveguide.We propose to use the nonlinear optical process of spontaneous parametric down-conversion(SPDC)and a well-designed lithium niobate waveguide structure to generate a hyperentangled(in the polarization dimension and the energy-time dimension)two-photon state.By performing numerical simulations of the waveguide structure and calculating the possible polarization states,joint spectral amplitudes(JSA),and joint temporal amplitudes(JTA)of the generated photon pair,we show that the generated photon pair is indeed hyperentangled in both the polarization dimension and the energy-time dimension.
文摘In this paper,we present a novel method for the complete analysis of maximally hyperentangled state of photon system in two degrees of freedom(DOFs),resorting to the auxiliary high-dimensional entanglement in the third DOF.This method not only can be used for complete hyperentangled Bell state analysis of two-photon system,but also can be suitable for complete hyperentangled Greenberger-Horne-Zeilinger(GHZ)state analysis of three-photon system,and can be extended to the complete Nphoton hyperentangled GHZ state analysis.In our approach,the parity information of hyperentanglement is determined via the measurement on evolved auxiliary high-dimensional entanglement,and the relative phase information of hyperentanglement is determined via the projective measurement.Moreover,this approach can be accomplished by just using linear optics,and is significant for the investigation of photonic hyperentangled state analysis.
基金This work was supported by the National Natural Science Foundation of China under Grant No.11604012the Fundamental Research Funds for the Central Universities under Grant No.FRF-TP-19-011A3+2 种基金the National Natural Science Foundation of China under Contract 61901420the Shanxi Province Science Foundation for Youths under Contract No.201901D211235the Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi under Contract No.2019L0507。
文摘Hyperentangled Bell states analysis(HBSA)is an essential building block for certain hyper-parallel quantum information processing.We propose a complete and deterministic HBSA scheme encoded in spatial and polarization degrees of freedom(DOFs)of two-photon system assisted by a fixed frequency-based entanglement and a time interval DOF.The parity information the spatial-based and polarization-based hyper-entanglement can be distinguished by the distinct time intervals of the photon pairs,and the phase information can be distinguished by the detection signature.Compared with previous schemes,the number of the auxiliary entanglements is reduced from two to one by introducing time interval DOF.Moreover,the additional frequency and time interval DOFs suffer less from the collective channel noise.
基金supported in part by the National Natural Science Foundation of China(Grant Nos.12192252 and 12074155)The Foundation for Shanghai Municipal Science and Technology Major Project(Grant No.2019SHZDZX01-ZX06)+1 种基金Jiangxi Provincial Natural Science Foundation(Grants No.20212ACB201004,Grant No.20202ACBL211003)funding provided by Shanghai Jiao Tong University.
文摘Exploiting the fantastic features of quantum mechanics,a hyperentangled quantum network encoded in multiple degree of freedoms(DOF),e.g.,polarization and orbital angular momentum DOFs,can encode more qubits per transmitted photon and offers a promising platform for many dramatic applications.Here,we demonstrate such a hyperentangled multiuser network with a fully connected network architecture by using dense wavelength division multiplexing and entanglement transfer technique.Three hyperentangled states in polarization and time-energy DOFs are multiplexed to three single mode fibers to form the fully connected network architecture.Then,three interferometric quantum gates are utilized for transferring quantum entanglement from time-energy to orbital angular momentum DOF.The experimental results reveal a high quality of the hyperentanglement of the constructed network with the entangled state fidelity of higher than 96%.Our approach can provide a novel way to construct a large-scale hyperentangled network that can support various kinds of quantum tasks like superdense coding and teleportation.
基金supported by the National Natural Science Foundation of China(Grant No.11475021)the National Key Basic Research Program of China(Grant No.2013CB922000)
文摘Hyperentangled-Bell-state analysis(HBSA) is critical for high-capacity quantum communication. Based on a recent proposal by Wang et al. [Opt. Express 24, 28444(2016)], we design two independent schemes for error-heralded deterministic generation and self-assisted complete HBSA of two-photon systems entangled in both polarization and spatial-mode degrees of freedom(DOFs).Unlike previous programs, we firstly propose an error-heralded block with a singly charged quantum dot inside a single-sided optical microcavity, with which errors due to imperfect interactions between photons and quantum dot systems can be heralded.The error-heralded block, ensures that the fidelity of the two schemes for hyperentangled-Bell-state generation and complete HBSA reaches unity. Moreover, hyperentanglement makes it possible to analyze the polarization state with the assistance of the measured spatial-mode state. The self-assisted mechanism of HBSA greatly simplifies the analytical process and significantly relaxes the requirements of nonlinearities. Therefore, these schemes promise to be implemented more easily in experiments,taking a step closer to long-distance high-capacity quantum communication.
基金supported by the European Union through the project FP7-ICT-2011-9-600838(QWAD Quantum Waveguides Application and Developmentwww.qwad-project.eu)by FIRB,Futuro in Ricerca HYTEQ.
文摘Encoding many qubits in different degrees of freedom(DOFs)of single photons is one of the routes toward enlarging the Hilbert space spanned by a photonic quantum state.Hyperentangled photon states(that is,states showing entanglement in multiple DOFs)have demonstrated significant implications for both fundamental physics tests and quantum communication and computation.Increasing the number of qubits of photonic experiments requires miniaturization and integration of the basic elements,and functions to guarantee the setup stability,which motivates the development of technologies allowing the precise control of different photonic DOFs on a chip.We demonstrate the contextual use of path and polarization qubits propagating within an integrated quantum circuit.We tested the properties of four-qubit linear cluster states built on both DOFs,and we exploited them to perform the Grover's search algorithm according to the one-way quantum computation model.Our results pave the way toward the full integration on a chip of hybrid multi-qubit multiphoton states.
基金supported by the National Natural Science Foundation of China(Grant Nos.11974189,12175106,and 92365110)Postgraduate Research&Practice Innovation Program of Jiangsu Province(Grant No.KYCX23-1027)。
文摘Hyperentanglement, the simultaneous entanglement in more than one degree of freedom(DOF), plays an important role in quantum communication and quantum information processing for it can effectively increase the channel capacity. Existing hyperentanglement sources mainly focus on the generation of the hyperentanglement in two DOFs. In this paper, we design the generation protocols for three kinds of hyperentanglement encoded in three DOFs with the practical coherent pulses sources, including the polarization-frequency-space hyperentanglement, the polarization-frequency-time-bin hyperentanglement, and the polarizationspace-time-bin hyperentanglement. These protocols exploit the spontaneous parametric down-conversion(SPDC) process and the Sagnac interferometer. The three protocols are all based on feasible experimental condition and may have potential applications in future hyperentanglement-based quantum communication and quantum information processing protocols.
基金supported by the National Natural Science Foundation of China (Grant Nos. 11474027, 61675028, and 11674033)the Fundamental Research Funds for the Central Universities (Grant No. 2015KJJCA01)the National High Technology Research and Development Program of China(Grant No. 2013AA122902)
文摘This study proposes the first high-capacity quantum secure direct communication(QSDC) with two-photon six-qubit hyperentangled Bell states in two longitudinal momentum and polarization degrees of freedom(DOFs) of photon pairs, which can be generated using two 0.5 mm-thick type-I β barium borate crystal slabs aligned one behind the other and an eight-hole screen. The secret message can be independently encoded on the photon pairs with 64 unitary operations in all three DOFs. This protocol has a higher capacity than previous QSDC protocols because each photon pair can carry 6 bits of information, not just 2 or 4 bits.Our QSDC protocol decreases the influence of decoherence from environment noise by exploiting the decoy photons to check the security of the transmission of the first photon sequence. Compared with two-way QSDC protocols, our QSDC protocol is immune to an attack by an eavesdropper using Trojan horse attack strategies because it is a one-way quantum communication.The QSDC protocol has good applications in the future quantum communication because of all these features.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 61068001 and 11147174)
文摘We present a scheme for quantum superdense coding with hyperentanglement, in which the sender can transfer four bits of classical information by sending only one photon. The important device in the scheme is the hyperentangled Bell-state analyzer in both polarization and frequency degrees of freedom, which is also constructed in the paper by using a quantum nondemolition detector assisted by cross-Kerr nonlinearity. Our scheme can transfer more informationwith less resources than the existing schemes and is nearly deterministic and nondestructive.
基金supported by the Natural Science Foundation of Jiangsu Provincial Universities, China (Grant No. 10KJB180004)
文摘We propose a two-step quantum secure direct communication （QSDC） protocol with hyperentanglement in both the spatial-mode and the polarization degrees of freedom of photon pairs which can in principle be produced with a beta barium borate crystal. The secret message can be encoded on the photon pairs with unitary operations in these two degrees of freedom independently. This QSDC protocol has a higher capacity than the original two-step QSDC protocol as each photon pair can carry 4 bits of information. Compared with the QSDC protocol based on hyperdense coding, this QSDC protocol has the immunity to Trojan horse attack strategies with the process for determining the number of the photons in each quantum signal as it is a one-way quantum communication protocol.
基金Supported by the National Natural Science Foundations of China under Grant Nos. 10904066 and 11004096the State Key Program for Basic Research of China under Grant No. 2011CBA00205
文摘We propose two schemes for realizing quantum secure direct communication (QSDC)by using a set ofordered two-photon three-dimensional hyperentangled states entangled in two degrees of freedom (DOFs)as quantuminformation channels.In the first scheme,the photons from Bob to Alice are transmitted only once.After insuring thesecurity of the quantum channels,Bob encodes the secret message on his photons.Then Alice performs single-photontwo-DOF Bell bases measurements on her photons.This scheme has better security than former QSDC protocols.In thesecond scheme,Bob transmits photons to Alice twice.After insuring the security of the quantum channels,Bob encodesthe secret message on his photons.Then Alice performs two-photon Bell bases measurements on each DOF.The schemehas more information capacity than former QSDC protocols.
基金Supported by the Natural Science Foundation of Jiangsu Provincial Universities under Grant No.10KJB180004the National Natural Science Foundation of China under Grant No.11105075
文摘We propose a bidirectional quantum secure direct communication(QSDC) network protocol with the hyperentanglment in both the spatial-mode ad the polarization degrees of freedom of photon pairs which can in principle be produced with a beta barium borate crystal.The secret message can be encoded on the photon pairs with unitary operations in these two degrees of freedom independently.Compared with other QSDC network protocols,our QSDC network protocol has a higher capacity as each photon pair can carry 4 bits of information.Also,we discuss the security of our QSDC network protocol and its feasibility with current techniques.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11974189 and 12175106)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(Grant No.20KJB140001)the Postgraduate Research&Practice Innovation Program of Jiangsu Province,China(Grand No.KYCX22-0963)
文摘The one-step quantum secure direct communication(QSDC)(Sci.Bull.67,367(2022))can effectively simplify QSDC’s operation and reduce message loss.For enhancing its security under practical experimental condition,we propose two measurement-device-independent(MDI)one-step QSDC protocols,which can resist all possible attacks from imperfect measurement devices.In both protocols,the communication parties prepare identical polarization-spatial-mode two-photon hyperentangled states and construct the hyperentanglement channel by hyperentanglement swapping.The first MDI one-step QSDC protocol adopts the nonlinear-optical complete hyperentanglement Bell state measurement(HBSM)to construct the hyperentanglement channel,while the second protocol adopts the linear-optical partial HBSM.Then,the parties encode the photons in the polarization degree of freedom and send them to the third party for the hyperentanglementassisted complete polarization Bell state measurement.Both protocols are unconditionally secure in theory.The simulation results show the MDI one-step QSDC protocol with complete HBSM attains the maximal communication distance of about354 km.Our MDI one-step QSDC protocols may have potential applications in the future quantum secure communication field.
基金supported by the National Natural Science Foundation of China(Grant No.61402058)the Science and Technology Support Project of Sichuan Province,China(Grant No.2013GZX0137)+1 种基金the Fund for Young Persons Project of Sichuan Province,China(Grant No.12ZB017)the Foundation of Cyberspace Security Key Laboratory of Sichuan Higher Education Institutions,China(Grant No.szjj2014-074)
文摘Higher channel capacity and security are difficult to reach in a noisy channel. The loss of photons and the distortion of the qubit state are caused by noise. To solve these problems, in our study, a hyperentangled Bell state is used to design faithful deterministic secure quantum communication and authentication protocol over collective-rotation and collective-dephasing noisy channel, which doubles the channel capacity compared with using an ordinary Bell state as a carrier; a logical hyperentangled Bell state immune to collective-rotation and collective-dephasing noise is constructed. The secret message is divided into several parts to transmit, however the identity strings of Alice and Bob are reused. Unitary operations are not used.
基金Project supported by the National Natural Science Foundation of China(Grant No.11604226)Science and Technology Program Foundation of the Beijing Municipal Commission of Education of China(Grants No.CIT&TCD201904080).
文摘We present a deterministic nondestructive hyperentangled Bell state analysis protocol for photons entangled in three degrees of freedom(DOFs),including polarization,spatial-mode,and time-bin DOFs.The polarization Bell state analyzer and spatial-mode Bell state analyzer are constructed by polarization parity-check quantum nondemolition detector(P-QND)and spatial-mode parity-check quantum nondemolition detector(S-QND)using cross-Kerr nonlinearity,respectively.The time-bin Bell state analyzer is constructed by the swap gate for polarization state and time-bin state of a photon(P-T swap gate)and P-QND.The Bell states analyzer for one DOF will not destruct the Bell states of other two DOFs,so the polarization-spatial-time-bin hyperentangled Bell states can be determinately distinguished without destruction.This deterministic nondestructive state analysis method has useful applications in quantum information protocols.
