Rate limits in quantum networks with lossy repeaters

The derivation of ultimate limits to communication over certain quantum repeater networks have provided extremely valuable benchmarks for assessing near-term protocols. However, these bounds are usually derived in the limit ideal devices and leave questions about performance practical implementations unanswered. To address this challenge, we quantify how presence loss stations affect maximum attainable rates linear chains more complex networks. Extending framework node splitting, model introduced at then prove corresponding limits. In chain scenario show that, by increasing number stations, rate cannot overcome a quantity, which solely depends on single station. We introduce way adapting standard machinery obtaining realistic scenario. difference is that whilst any strategy can be given fixed channel, when repeaters additional decoherence, effective overall channel itself function chosen (e.g., one-way versus two-way classical communication). Classes strategies analysed using modeling subsequent interpreted as optimal within class.