Demonstration of a photonic router via quantum walks

Abstract

Motivated by the need for quantum computers to communicate between multiple, well separated qubits, we introduce the task of routing the quantum state from one input mode to a superposition of several output modes coherently. We report an experimental demonstration of a deterministic photonic routing protocol applied to an entangled state. We show in a quantum walk architecture, quantum networks perfectly route entangled states from an initial input mode to an arbitrary output mode coherently and deterministically. Our results demonstrate the key principle of a perfect router, opening a route toward data routing and transferring for quantum computing systems. Our work paves the way for effective design of efficient routing protocols on practical quantum networks.

Quantum walk-based protocol for secure communication between any two directly connected nodes on a network

“…Since quantum walks have also been experimentally realized in several systems, [69][70][71] and the operations which we have used are all unitaries, it is indicative that the protocol proposed in this study is experimentally realizable.…”