Intracity Quantum Communication via Thermal Microwave Networks
Ze-Liang Xiang, Mengzhen Zhang, Liang Jiang, Peter Rabl · Physical Review X · 2017
Communication over proven-secure quantum channels is potentially one of the most wide-ranging applications of currently developed quantum technologies.It is generally envisioned that in future quantum networks, separated nodes containing stationary solid-state or atomic qubits are connected via the exchange of optical photons over large distances.In this work, we explore an intriguing alternative for quantum communication via all-microwave networks.To make this possible, we describe a general protocol for sending quantum states through thermal channels, even when the number of thermal photons in the channel is much larger than 1.The protocol can be implemented with state-of-the-art superconducting circuits and enables the transfer of quantum states over distances of about 100 m via microwave transmission lines cooled to only T ¼ 4 K.This opens up new possibilities for quantum communication within and across buildings and, consequently, for the implementation of intracity quantum networks based on microwave technology only.