Faithful and deterministic teleportation of an arbitrary $N$-qubit state using and identifying only Bell states

Abstract

First, I show explicitly a scheme to {\it faithfully} and {\it deterministically} teleport an arbitrary 2-qubit state from Alice to Bob. In this scheme two same Bell states are sufficient for use. Bob can recover the 2-qubit state by performing at most 4 single-qubit unitary operations conditioned on Alice's 4-bit classical public message corresponding to her two Bell-state measurement outcomes. Then I generalize the 2-qubit teleportation scheme to an aribitrary $N(N\ge 3)$-qubit state teleportation case by using $N$ same Bell states. In the generalized scheme, Alice only needs to identify $N$ Bell states after quantum swapping and then publish her measurement outcomes ($2N$-bit classical message). Conditioned on Alice's $2N$-bit classical message, Bob only needs to perform at most $2N$ single-qubit unitary operations to {\it fully} recover the arbitrary state. By comparing with the newest relevant work [Phys. Rev. A{\bf 71}, 032303(2005)], the advantages of the present schemes are revealed, respectively.