Biphoton entanglement of topologically distinct modes

Abstract

The robust generation and manipulation of entangled multiphoton states on chip has an essential role in quantum computation and communication. Lattice topology has emerged as a means of protecting photonic states from disorder, but entanglement across different topologies remains unexplored. We report biphoton entanglement between topologically distinct spatial modes in a bipartite array of silicon waveguides. The results highlight topology as an additional degree of freedom for entanglement and open avenues for investigating information teleportation between trivial and topological modes.