Fig. 3: Schematic of a nested swapping protocol.
From: Comparing one- and two-way quantum repeater architectures
We start with N elementary segments, each of length l0. The red boxes represent a swapping operation. Based on the decision variable \({{{{\mathcal{D}}}}}_{i}\), distillation may be performed before a swapping operation. Each swapping operation doubles the length of the link. This process is repeated until an end-to-end link is established.
