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arXiv · 1608.07465

Motion-Compensated Handheld Quantum Key Distribution System

Hyunchae Chun·Iris Choi·Grahame Faulkner·Larry Clarke·Bryan Barber·Glenn George·Colin Capon·Antti Niskanen·Joachim Wabnig·Dominic OBrien·David Bitauld
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Abstract

Mobile devices have become an inseparable part of our everyday life. They are used to transmit an ever-increasing amount of sensitive health, financial and personal information. This exposes us to the growing scale and sophistication of cyber-attacks. Quantum Key Distribution (QKD) can provide unconditional and future-proof data security but implementing it for handheld mobile devices comes with specific challenges. To establish security, secret keys of sufficient length need to be transmitted during the time of a handheld transaction (~1s) despite device misalignment, ambient light and user's inevitable hand movements. Transmitters and receivers should ideally be compact and low-cost, while avoiding security loopholes. Here we demonstrate the first QKD transmission from a handheld transmitter with a key-rate large enough to overcome finite key effects. Using dynamic beam-steering, reference-frame-independent encoding and fast indistinguishable pulse generation, we obtain a secret key rate above 30kb/s over a distance of 0.5m under ambient light conditions.

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Hyunchae Chun, Iris Choi, Grahame Faulkner, Larry Clarke, Bryan Barber, Glenn George, Colin Capon, Antti Niskanen, Joachim Wabnig, Dominic OBrien, David Bitauld. 2016-08-26. Motion-Compensated Handheld Quantum Key Distribution System. https://arxiv.org/abs/1608.07465

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