EPJ Quantum Technol. (2018) 5: 4
https://doi.org/10.1140/epjqt/s40507-018-0068-1

Research

Q³Sat: quantum communications uplink to a 3U CubeSat—feasibility & design

¹ Institute for Quantum Optics and Quantum Information Vienna, Vienna, Austria
² Vienna Center for Quantum Science and Technology, Vienna, Austria
³ University of Applied Sciences Wiener Neustadt, Wiener Neustadt, Austria
⁴ Laboratoire Interdisciplinaire de Physique, University Grenoble Alpes, Saint-Martin-d’Hères, France

^* e-mail: rupert.ursin@oeaw.ac.at

Received: 11 November 2017
Accepted: 20 March 2018
Published online: 27 April 2018

Abstract

Satellites are the most efficient way to achieve global scale quantum communication (Q.Com) because unavoidable losses restrict fiber based Q.Com to a few hundred kilometers. We demonstrate the feasibility of establishing a Q.Com uplink with a 3U CubeSat, measuring only 10 × 10 × 34 cm³, using commercial off-the-shelf components, the majority of which have space heritage. We demonstrate how to leverage the latest advancements in nano-satellite body-pointing to show that our 4 kg CubeSat can generate a quantum-secure key, which has so far only been shown by a much larger 600 kg satellite mission. A comprehensive link budget and simulation was performed to calculate the secure key rates. We discuss design choices and trade-offs to maximize the key rate while minimizing the cost and development needed. Our detailed design and feasibility study can be readily used as a template for global scale Q.Com.