Distributed Coherent Absorption in Quantum Networks for Deterministic Entanglement Generation

We show theoretically and demonstrate experimentally that coherent absorption of a single photon in a quantum network allows deterministic generation of entanglement between the network’s nodes. Quantum networks, consisting of multiple nodes connected by quantum channels, are in the basis of quantum technology allowing protocols of quantum computation and quantum communication. To implement these protocols, quantum entanglement should be distributed across the network. A conventional approach of entanglement generation is realized by a sequential splitting of a single photon on a series of beamsplitters and independent coupling of each ‘part’ of the photon into the corresponding node of the network [1] , Fig. 1(a) . Efficient entanglement generation in a large scale quantum network is a challenging task as a highly efficient light-matter interaction in each node of the network is required: even in a network of 100 nodes the probability of successful entanglement generation would be around 10 −5 .