Javier Rey-Domínguez

Most current proposals for entanglement distribution networks assume a connection-oriented approach, where resources along a path may be reserved before the start of the session. This strategy, however, does not match the common practice in the existing infrastructure for the Internet, which relies on connectionless packet switching. In our work, we study how a hop-by-hop teleportation can be used to perform entanglement distribution across a network without any prior resource reservation. Specifically, we investigate the attainable secret key generation rate between two users employing this protocol in a repeater chain setup. We analyze this scenario for deterministic quantum repeaters with and without encoding, where we consider a three-qubit repetition code for error detection in the former case. Typical models for the operational errors in these protocols are considered. Our results suggest that the usage of quantum error detection schemes will enable trust-free secret key distribution at distances of interest.

Quantum networks use platforms like quantum repeaters to enable quantum communications at arbitrary distances. Early quantum networks are expected to be deployed on pre-existing infrastructure, sharing resources with classical networks, and thus can benefit from compatible design principles and behaviours. In particular, most of the research on quantum repeater networks based on entanglement distribution assume that some connection is established in order to reserve resources for the distribution attempt. However, the most prominent classical network, the Internet, is built upon the concept of connectionless communications, and therefore this approach might not be ideal for the early stages of deployment. In our work, we investigate the performance of connectionless protocols over quantum networks. To do so, we consider both unencoded (standard) but deterministic repeaters, and repeaters using a 3-quit repetition code. We analyse the achievable secret key rates for both of these setups in different regimes of errors. Our results suggest that error correction techniques such as the usage of encoded quantum repeaters will be crucial to the success of early quantum networks.