Assessing the Practicality of a Simple Multi-node Quantum Repeater

Abstract

This thesis assesses the theoretical performance of a realistic multi-node quantum repeater that is implementable with current technology. A quantum repeater, by definition, allows for communication rates in a channel to be larger than what is fundamentally possible over a loss only channel. We consider a simple, one-way, multi-node quantum repeater that utilizes entanglement swapping in the absence of any quantum error correction or entanglement purification. We create a theoretical model of the quantum repeater, incorporating the imperfections of each component within the system, to get an accurate key rate using current, viable state-of-the-art experimental parameters. Our main goal is to benchmark the performance of this specific multi-node quantum repeater. We compare the performance of this multi-node system to that of a single node repeater, which has been previously analysed for this architecture. We are interested to see if there is an advantage for introducing more nodes in this type of system. We also provide some suggestions for improving the key rate performance.