We propose a protocol for transferring photons of unknown states to a distant location using path-polarization hybrid entanglement.Our protocol uses a polarizing beam splitter(PBS),a beam splitter(BS),a CNOT-operation...We propose a protocol for transferring photons of unknown states to a distant location using path-polarization hybrid entanglement.Our protocol uses a polarizing beam splitter(PBS),a beam splitter(BS),a CNOT-operation,four unitary operations and polarizing detectors.In our protocol,the hybrid entangled states are generated by the PBS,and it is transmitted through the quantum channel containing the BS and CNOT-gate.The measurement results of the polarizing detectors and classical communications determine which unitary operation will be used in the last step for recovering initial states.The security of the channel in transmitting unknown photons between two parties is confirmed by the results of the measurement of each target photon in the control mode.展开更多
We propose a quantum secure direct communication protocol with entanglement swapping and hyperentanglement. Any two users, Alice and Bob, can communicate with each other in a quantum network, even though there is no d...We propose a quantum secure direct communication protocol with entanglement swapping and hyperentanglement. Any two users, Alice and Bob, can communicate with each other in a quantum network, even though there is no direct quantum channel between them. The trust center, Trent, who provides a quantum channel to link them by performing entanglement swapping, cannot eavesdrop on their communication. This protocol provides a high channel capacity because it uses hyperentanglement, which can be generated using a beta barium borate crystal.展开更多
We would like to make some modifications on our protocol[1]in order to receive ideas in regards to the comments[2]made by Liu et al.about our paper.In the comment,they raised three weak points in regard to our protoco...We would like to make some modifications on our protocol[1]in order to receive ideas in regards to the comments[2]made by Liu et al.about our paper.In the comment,they raised three weak points in regard to our protocols.First,they pointed out that either Bob or Charlie may,without their cooperation,gain some bit of shared information sent by Trent in our first and second protocols.Second,Alice’s secret information can be eavesdropped by Trent in the second protocol.Lastly,Trent can disturb communication because there is no message authentication in our second protocol.We suggest a few modifications in each protocol to make up for these weaknesses.展开更多
A multiuser quantum direct communication network system for N users utilizing χ-type entangled states is prupused. The network system is composed of a communication center,N users,and N quantum lines linking the cent...A multiuser quantum direct communication network system for N users utilizing χ-type entangled states is prupused. The network system is composed of a communication center,N users,and N quantum lines linking the center and the N users.There is no quantum line among users,and therefore only N quantum lines are necessary for communication between users.Using one χ-type entangled state, in this protocol we are able to send two bits of information through direct communication and,at the same time,share two bits of quantum keys. The security of the protocol is then analyzed.展开更多
基金the MKE(The Ministry of Know ledge Economy),Korea under the ITRC(Information Technology Research Center)support program(NIPA-2012-H0301-12-3007)supervised by the NIPA(National IT Industry Prormotion A gency).
文摘We propose a protocol for transferring photons of unknown states to a distant location using path-polarization hybrid entanglement.Our protocol uses a polarizing beam splitter(PBS),a beam splitter(BS),a CNOT-operation,four unitary operations and polarizing detectors.In our protocol,the hybrid entangled states are generated by the PBS,and it is transmitted through the quantum channel containing the BS and CNOT-gate.The measurement results of the polarizing detectors and classical communications determine which unitary operation will be used in the last step for recovering initial states.The security of the channel in transmitting unknown photons between two parties is confirmed by the results of the measurement of each target photon in the control mode.
基金supported by the Ministry of Knowledge Economy,Korea,under the Information Technology Research Center(ITRC)support program(NIPA-2013H0301-13-3007)supervised by the National IT Industry Promotion Agencythe Research Foundation of Korea University
文摘We propose a quantum secure direct communication protocol with entanglement swapping and hyperentanglement. Any two users, Alice and Bob, can communicate with each other in a quantum network, even though there is no direct quantum channel between them. The trust center, Trent, who provides a quantum channel to link them by performing entanglement swapping, cannot eavesdrop on their communication. This protocol provides a high channel capacity because it uses hyperentanglement, which can be generated using a beta barium borate crystal.
基金Supported by the Ministry of Knowledge Economy of Korea under Grant No NIPA-2013-H0301-13-3007.
文摘We would like to make some modifications on our protocol[1]in order to receive ideas in regards to the comments[2]made by Liu et al.about our paper.In the comment,they raised three weak points in regard to our protocols.First,they pointed out that either Bob or Charlie may,without their cooperation,gain some bit of shared information sent by Trent in our first and second protocols.Second,Alice’s secret information can be eavesdropped by Trent in the second protocol.Lastly,Trent can disturb communication because there is no message authentication in our second protocol.We suggest a few modifications in each protocol to make up for these weaknesses.
基金Supported by the MKE(The Ministry of Knowledge Economy),Korea,under the ITRC(Information Technology Research Center)support program(NIPA2012H0301123007)supervised by the NIPA(National IT Industry Promotion Agency)(NIPA-2011-C1090-1101-0004).
文摘A multiuser quantum direct communication network system for N users utilizing χ-type entangled states is prupused. The network system is composed of a communication center,N users,and N quantum lines linking the center and the N users.There is no quantum line among users,and therefore only N quantum lines are necessary for communication between users.Using one χ-type entangled state, in this protocol we are able to send two bits of information through direct communication and,at the same time,share two bits of quantum keys. The security of the protocol is then analyzed.
