We propose genuine （k, m）-threshold controlling schemes for controlled teleportation via multi-particle entangled states, where the teleportation of a quantum state from a sender （Alice） to a receiver （Bob） is u...We propose genuine （k, m）-threshold controlling schemes for controlled teleportation via multi-particle entangled states, where the teleportation of a quantum state from a sender （Alice） to a receiver （Bob） is under the control of m supervisors such that k （k≤ m） or more of these supervisors can help Bob recover the transferred state. By construction, anyone of our quantum channels is a genuine multipartite entangled state of which any two parts are inseparable. Their properties are compared and contrasted with those of the well-known GHZ, W, and linear cluster states, and also several other genuine multipartite entangled states recently introduced in the literature.展开更多
In this paper, we show that a(2, 3) discrete variable threshold quantum secret sharing scheme of secure direct communication can be achieved based on recurrence using the same devices as in BB84. The scheme is devised...In this paper, we show that a(2, 3) discrete variable threshold quantum secret sharing scheme of secure direct communication can be achieved based on recurrence using the same devices as in BB84. The scheme is devised by first placing the shares of smaller secret pieces into the shares of the largest secret piece, converting the shares of the largest secret piece into corresponding quantum state sequences, inserting nonorthogonal state particles into the quantum state sequences with the purpose of detecting eavesdropping, and finally sending the new quantum state sequences to the three participants respectively. Consequently, every particle can on average carry up to 1.5-bit messages due to the use of recurrence. The control codes are randomly prepared using the way to generate fountain codes with pre-shared source codes between Alice and Bob, making three participants can detect eavesdropping by themselves without sending classical messages to Alice. Due to the flexible encoding, our scheme is also dynamic, which means that it allows the participants to join and leave freely.展开更多
The quantum teleportation with the entangled thermai state is investigated based on the completely anisotropie Heisenberg chain in the presence of the externally inhomogeneous magnetic field. The effects of the anisot...The quantum teleportation with the entangled thermai state is investigated based on the completely anisotropie Heisenberg chain in the presence of the externally inhomogeneous magnetic field. The effects of the anisotropy and magnetic field for the quantum fidelity are studied in detail The zero temperature limit and the features of the nonzero temperature for this nonclassical fdelity are obtained. We find that the quantum teleportation demands more stringent conditions than the therma/ entanglement of the resource by investigating the threshold temperature of the thermal concurrence and the criticai temperature of the maximai teleportation fidelity. The useful quantum teleportation should avoid the point of the phase transition of the system and the anisotropy of the chain and the external magnetic field can control the applicability of the resource in the quantum teleportation.展开更多
基金Supported by National Natural Science Foundation of China under Grant Nos.11004050 and 10874019Key Project of Chinese Ministry of Education under Grant No.211119+2 种基金Scientific Research Fund of Hunan Provincial Education Department of China under Grant Nos.10B013 and 09A013Excellent Talents Program of Hengyang Normal University of China under Grant No.2010YCJH01Science Foundation of Hengyang Normal University of China under Grant No.10B69
文摘We propose genuine （k, m）-threshold controlling schemes for controlled teleportation via multi-particle entangled states, where the teleportation of a quantum state from a sender （Alice） to a receiver （Bob） is under the control of m supervisors such that k （k≤ m） or more of these supervisors can help Bob recover the transferred state. By construction, anyone of our quantum channels is a genuine multipartite entangled state of which any two parts are inseparable. Their properties are compared and contrasted with those of the well-known GHZ, W, and linear cluster states, and also several other genuine multipartite entangled states recently introduced in the literature.
基金Supported in part by an International Macquarie University Research Excellence Scholarship(i MQRES),Australian Research Council Grant DP0987734also supported by the National Basic Research Program of China(973 Program)under Grant No.2010CB923200+2 种基金the National Natural Science Foundation of China under No.61377067Fund of State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications,China,National Natural Science Foundation of China under Grant Nos.61202362,61262057,61472433China Postdoctora Science Foundation under Grant No.2013M542560
文摘In this paper, we show that a(2, 3) discrete variable threshold quantum secret sharing scheme of secure direct communication can be achieved based on recurrence using the same devices as in BB84. The scheme is devised by first placing the shares of smaller secret pieces into the shares of the largest secret piece, converting the shares of the largest secret piece into corresponding quantum state sequences, inserting nonorthogonal state particles into the quantum state sequences with the purpose of detecting eavesdropping, and finally sending the new quantum state sequences to the three participants respectively. Consequently, every particle can on average carry up to 1.5-bit messages due to the use of recurrence. The control codes are randomly prepared using the way to generate fountain codes with pre-shared source codes between Alice and Bob, making three participants can detect eavesdropping by themselves without sending classical messages to Alice. Due to the flexible encoding, our scheme is also dynamic, which means that it allows the participants to join and leave freely.
基金Supported by the Special Research Fund Provided by the Chonnam National University
文摘The quantum teleportation with the entangled thermai state is investigated based on the completely anisotropie Heisenberg chain in the presence of the externally inhomogeneous magnetic field. The effects of the anisotropy and magnetic field for the quantum fidelity are studied in detail The zero temperature limit and the features of the nonzero temperature for this nonclassical fdelity are obtained. We find that the quantum teleportation demands more stringent conditions than the therma/ entanglement of the resource by investigating the threshold temperature of the thermal concurrence and the criticai temperature of the maximai teleportation fidelity. The useful quantum teleportation should avoid the point of the phase transition of the system and the anisotropy of the chain and the external magnetic field can control the applicability of the resource in the quantum teleportation.
