We first propose a scheme for preparing the genuine Yeo-Chua 4-qubit entangled state via cavity QED. Using the genuine Yeo-Chua atomic state, we further propose a cavity QED scheme for teleporting an arbitrary two-atom state. In two schemes the large-detuning is chosen and the necessary time is designed to be much shorter than Rydberg-atom’s lifespan. Both schemes share the distinct advantage that cavity decay and atom decay can be neglected. As for the interaction manipulation, our preparation scheme is more feasible than a recent similar one. Compared with the Yeo and Chua’s scheme, our teleportation scheme has significantly reduced the measuring difficulty.
A symmetric and(n,n)-threshold scheme for a sender to partition his/her arbitrary single-qubit information among n recipients is proposed by using a newly constructed asymmetric(n+1)-qubit W state.Both the scheme in some given scenarios and the new W state are also discussed given.
A simpler criterion is presented to judge whether a W state can be taken as quantum channel forperfectly splitting or teleporting an arbitrary single-qubit state. If the W state is usable,the detailed manipulations in the two quantum information processes are amply shown. Moreover,some relevant discussions are made.
This paper proposes a scheme for implementing the teleportation of an arbitrary unknown two-atom state by using a cluster state of four identical 2-level atoms as quantum channel in a thermal cavity. The two distinct advantages of the present scheme are： （i） The discrimination of 16 orthonormal cluster states in the standard teleportation protocol is transformed into the discrimination of single-atom states. Consequently, the discrimination difficulty of states is degraded. （ii） The scheme is insensitive to the cavity field state and the cavity decay for the thermal cavity is only virtually excited when atoms interact with it. Thus, the scheme is more feasible.
The perfect teleportation of an arbitrary three-qubit state with the highly entangled six-qubit genuine state introduced by Borras et al.(J.Phys.A: Math.Theor.40 (2007) 13407) is studied.Some appropriate measuring bases the sender can take and the corresponding unitary operations the receiver should execute in terms of the sender’s measurement outcome are explicitly given.The flexibility between the measurement difficulty and the reconstruction difficulty is shown.Moreover,discussions and comparisons between our scheme and the recent incomplete scheme (Choudhury et al,J.Phys.A: Math.Theor.42 (2009) 115303) are made.
YIN XiaoFeng 1,LIU YiMin 2,ZHANG ZiYun 1,ZHANG Wen 1 & ZHANG ZhanJun 1 1 Key Laboratory of Optoelectronic Information Acquisition & Manipulation of Ministry of Education of China,School of Physics & Material Science,Anhui University,Hefei 230039,China
A criterion for whether a pure-state quantum channel consisting of 2n qubits averagely distributed between two nodes can be used for perfectly teleporting an arbitrary n-qubit state via Bell-state measurements is educed.Specifically,a matrix is composed of the coefficients of the known channel state and whether the matrix is unitary decides the criterion.As the criterion is apparently different from the usual standard entanglement criterion (USEC),its applicability is enlarged and verified by other measuring bases.Thorough analyses have further simplified the resultant criterion,so that a much simpler criterion than the USEC is conclusively obtained.Moreover,the flexibility of operation complexity between the non-unitary measurements and the unitary reconstructions is explicitly exhibited.
ZUO XueQin 1,LIU YiMin 2,ZHANG ZiYun 1,ZHANG Wen 1 & ZHANG ZhanJun 1 1 Key Laboratory of Optoelectronic Information Acquisition & Manipulation of Ministry of Education of China,School of Physics & Material Science,Anhui University,Hefei 230039,China
