Drone-based Quantum Key Distribution (QKD)

Due to their effortless reconfigurability, expanded accessibility, rapid deployment, and capacity to traverse versatile environments, Unmanned Aerial Vehicles (UAVs) have seen increased utilization across numerous industries, leading to various novel applications. These range between law enforcement, disaster relief, consumer deliveries, and geographic mapping, with new applications continually appearing. With a growing demand for UAV-based services comes a growing concern for the safety and security of UAV operations. In contrast to classical approaches, quantum communication protocols provide the ability to transmit provably secure messages. Current quantum cryptography implementations focus on fiber-based or fixed free-space point-to-point channels. We seek to develop the emerging technology of UAVs to realize a free-space optical quantum channel that can exchange quantum-secured random keys over distances up to 10 km between two drones in flight. Here, we present progress on the development and deployment of the QKD source and the Pointing, Acquisition and Tracking (PAT) system, while overcoming the challenges presented by the Size, Weight, and Power (SWaP) constraints of the drone. Preliminary results yield a table-top Quantum Bit Error Rate (QBER) of 7.5% along with an in-flight classical channel loss of 20.6 dB. Mobile free-space quantum-secured communication platforms are an integral part of developing an expansive quantum communication network.