Two avowable quantum communication schemes are proposed.One is an avowable teleportation protocolbased on the quantum cryptography.In this protocol one teleports a set of one-particle states based on the availabilityo...Two avowable quantum communication schemes are proposed.One is an avowable teleportation protocolbased on the quantum cryptography.In this protocol one teleports a set of one-particle states based on the availabilityof an honest arbitrator,the keys and the Einstein-Podolsky-Rosen pairs shared by the communication parties and thearbitrator.The key point is that the fact of the teleportation can neither be disavowed by the sender nor be denied bythe receiver.Another is an avowable quantum secure direct communication scheme.A one-way Hash function chosenby the communication parties helps the receiver to validate the truth of the information and to avoid disavowing for thesender.展开更多
We suggest a method for transferring an unknown quantum state. In this method the sender Alice first applies a controlled-not operation on the particle in the unknown quantum state and an ancillary particle which she ...We suggest a method for transferring an unknown quantum state. In this method the sender Alice first applies a controlled-not operation on the particle in the unknown quantum state and an ancillary particle which she wants to send to the receiver Bob. Then she sends the ancillary particle to Bob. When Alice is informed by Bob that the ancillary particle is received, she performs a local measurement on her particle and sends Bob the outcome of the local measurement via a classical channel. Depending on the outcome Bob can restore the unknown quantum state, which Alice destroyed, on the ancillary particle successfully. As an application of this method we propose a quantum secure direct communication protocol. By introducing the decoy qubits the security of the scheme is guaranteed.展开更多
We present a scheme for perfectly teleporting a two-qubit entangled state via two parallel W state channels.The scheme consists of a positive operator valued measurement(POVM),classical communication and the correspon...We present a scheme for perfectly teleporting a two-qubit entangled state via two parallel W state channels.The scheme consists of a positive operator valued measurement(POVM),classical communication and the corresponding local unitary operation.How to realize the POVM using unitary operation and projective measurement is explicitly designed.展开更多
Au approximate instantaneous eigenstate is presented for the many-spin system possessing the anisotropy exchange interaction in a strong magnetic field by the perturbation method.Based on the instantaneous eigenstate,...Au approximate instantaneous eigenstate is presented for the many-spin system possessing the anisotropy exchange interaction in a strong magnetic field by the perturbation method.Based on the instantaneous eigenstate,the Berry phase of this state is worked out.Furthermore,the effect of the anisotropy exchange interaction on the Berry phase of the state for the many-spin system is studied.展开更多
基金supported by National Natural Science Foundation of China under Grant No.10671054Natural Science Foundation of Hebei Province of China under Grant No.07M006the Key Project of Science and Technology Research of the Ministry of Education under Grant No.207011
文摘Two avowable quantum communication schemes are proposed.One is an avowable teleportation protocolbased on the quantum cryptography.In this protocol one teleports a set of one-particle states based on the availabilityof an honest arbitrator,the keys and the Einstein-Podolsky-Rosen pairs shared by the communication parties and thearbitrator.The key point is that the fact of the teleportation can neither be disavowed by the sender nor be denied bythe receiver.Another is an avowable quantum secure direct communication scheme.A one-way Hash function chosenby the communication parties helps the receiver to validate the truth of the information and to avoid disavowing for thesender.
基金The project supported by the National Natural Science Foundation of China under Grant No. 10671054 and the Natural Science Foundation of Hebei Province under Grant Nos. A2004000141 and A2005000140
文摘We suggest a method for transferring an unknown quantum state. In this method the sender Alice first applies a controlled-not operation on the particle in the unknown quantum state and an ancillary particle which she wants to send to the receiver Bob. Then she sends the ancillary particle to Bob. When Alice is informed by Bob that the ancillary particle is received, she performs a local measurement on her particle and sends Bob the outcome of the local measurement via a classical channel. Depending on the outcome Bob can restore the unknown quantum state, which Alice destroyed, on the ancillary particle successfully. As an application of this method we propose a quantum secure direct communication protocol. By introducing the decoy qubits the security of the scheme is guaranteed.
基金by the National Natural Science Foundation of China under Grant Nos 10971247 and 10905016the Hebei Natural Science Foundation of China under Grant Nos F2009000311 and A2010000344the Science Foundation of Hebei Normal University under Grant No L2010Q04.
文摘We present a scheme for perfectly teleporting a two-qubit entangled state via two parallel W state channels.The scheme consists of a positive operator valued measurement(POVM),classical communication and the corresponding local unitary operation.How to realize the POVM using unitary operation and projective measurement is explicitly designed.
基金Supported by Hebei Natural Science Foundation under Grant No.196164.
文摘Au approximate instantaneous eigenstate is presented for the many-spin system possessing the anisotropy exchange interaction in a strong magnetic field by the perturbation method.Based on the instantaneous eigenstate,the Berry phase of this state is worked out.Furthermore,the effect of the anisotropy exchange interaction on the Berry phase of the state for the many-spin system is studied.
