Quantum private comparison is an important topic in quantum cryptography.Recently,the idea of semi-quantumness has been often used in designing private comparison protocol,which allows some of the participants to rema...Quantum private comparison is an important topic in quantum cryptography.Recently,the idea of semi-quantumness has been often used in designing private comparison protocol,which allows some of the participants to remain classical.In this paper,we propose a semi quantum private comparison scheme based on Greenberge-Horne-Zeilinger(GHZ)class states,which allows two classical participants to compare the equality of their private secret with the help of a quantum third party(server).In the proposed protocol,server is semi-honest who will follow the protocol honestly,but he may try to learn additional information from the protocol execution.The classical participants’activities are restricted to either measuring a quantum state or reflecting it in the classical basis{0,1}.In addition,security and efficiency of the proposed schemes have been discussed.展开更多
We propose two physical schemes, which can teleport unknown atomic entangled states from user A （Alice） to user B （Bob） via GHZ class states as quantum channel The two schemes are both based on cavity QED techniqu...We propose two physical schemes, which can teleport unknown atomic entangled states from user A （Alice） to user B （Bob） via GHZ class states as quantum channel The two schemes are both based on cavity QED techniques. In the two schemes, teleportation and distillation procedures can be realized simultaneously. The second teleportation scheme is more advantageous than the first one.展开更多
We present,two schemes for concentrating unknown nonmaximally entangled Greenberger Horme-Zeilinger(GHZ) or W class states.The first scheme for concentrating the nonmaximally entangled GHZ state is based on linearopti...We present,two schemes for concentrating unknown nonmaximally entangled Greenberger Horme-Zeilinger(GHZ) or W class states.The first scheme for concentrating the nonmaximally entangled GHZ state is based on linearoptical devices.The second scheme for concentrating the W class states can be applied to a wide variety of atomic state.Both of our schemes are not postselection ones and are within the current technologies.展开更多
We investigate the controlled implementation of a non-local CNOT operation using a three-qubit entangled state. Firstly, we show how the non-local CNOT operation can be implemented with unit fidelity and unit probabil...We investigate the controlled implementation of a non-local CNOT operation using a three-qubit entangled state. Firstly, we show how the non-local CNOT operation can be implemented with unit fidelity and unit probability by using a maximally entangled GHZ state as controlled quantum channel. Then, we put forward two schemes for conclusively implementing the non-local operation with unit fidelity by employing a partially entangled pure GHZ state as quantum channel. The feature of these schemes is that a third side is included, who may participate the process of quantum non-local implementation as a supervisor. Furthermore, when the quantum channel is partially entangled,the third one can rectify the state distorted by imperfect quantum channel. In addition to the GHZ class state, the W class state can also be used to implement the same non-local operation probabilistically. The probability of successful implementation using the W class state is always less than that using the GHZ class state.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.61572086)Major Project of Education Department in Sichuan(Grant No.18ZA0109)Web Culture Project Sponsored by the Humanities and Social Science Research Base of the Sichuan Provincial Education Department(Grant No.WLWH18-22).
文摘Quantum private comparison is an important topic in quantum cryptography.Recently,the idea of semi-quantumness has been often used in designing private comparison protocol,which allows some of the participants to remain classical.In this paper,we propose a semi quantum private comparison scheme based on Greenberge-Horne-Zeilinger(GHZ)class states,which allows two classical participants to compare the equality of their private secret with the help of a quantum third party(server).In the proposed protocol,server is semi-honest who will follow the protocol honestly,but he may try to learn additional information from the protocol execution.The classical participants’activities are restricted to either measuring a quantum state or reflecting it in the classical basis{0,1}.In addition,security and efficiency of the proposed schemes have been discussed.
文摘We propose two physical schemes, which can teleport unknown atomic entangled states from user A （Alice） to user B （Bob） via GHZ class states as quantum channel The two schemes are both based on cavity QED techniques. In the two schemes, teleportation and distillation procedures can be realized simultaneously. The second teleportation scheme is more advantageous than the first one.
基金The project supported by National Natural Science Foundation of Chinathe National Fundamental Research Program under Grant No.2006CB921900
文摘We present,two schemes for concentrating unknown nonmaximally entangled Greenberger Horme-Zeilinger(GHZ) or W class states.The first scheme for concentrating the nonmaximally entangled GHZ state is based on linearoptical devices.The second scheme for concentrating the W class states can be applied to a wide variety of atomic state.Both of our schemes are not postselection ones and are within the current technologies.
文摘We investigate the controlled implementation of a non-local CNOT operation using a three-qubit entangled state. Firstly, we show how the non-local CNOT operation can be implemented with unit fidelity and unit probability by using a maximally entangled GHZ state as controlled quantum channel. Then, we put forward two schemes for conclusively implementing the non-local operation with unit fidelity by employing a partially entangled pure GHZ state as quantum channel. The feature of these schemes is that a third side is included, who may participate the process of quantum non-local implementation as a supervisor. Furthermore, when the quantum channel is partially entangled,the third one can rectify the state distorted by imperfect quantum channel. In addition to the GHZ class state, the W class state can also be used to implement the same non-local operation probabilistically. The probability of successful implementation using the W class state is always less than that using the GHZ class state.
