A new kind of flexible quantum teleportation of an arbitrary multi-qubit state by multi-walker quantum walks

Quantum walks have emerged as an interesting approach to implementing quantum information processing task in recent years. In this work, we take advantage of the properties of quantum walks to design a novel kind of flexible and conclusive quantum teleportation scheme of multiple arbitrary qubits. First, two-walker quantum walks on three types of quantum structures, the line, the cycle and two-vertice complete graph with loops, are utilized to accomplish the teleportation of an arbitrary 2-qubit state. Second, without loss of generality, a generalization for teleporting an arbitrary N-qubit state is also shown by N-walker quantum walks on two-vertice complete graph with loops. Our scheme has two merits. (i) Three different quantum-walk structures can be used to teleport an arbitrary N-qubit state, which means that one can implement the scheme flexibly, depending on the concrete experimental environment. (ii) The prior entangled state is not necessarily prepared, as multiple-walker quantum walks may contain entanglement. In addition, the single-particle projective measurement and single-qubit gate are required, rather than a joint measurement and controlled-NOT gate, which will possibly simplify experimental realizations of this scheme. This work stimulates us to explore more potential applications of multi-walker quantum walks.