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arXiv · 2111.06186

Steering-based randomness certification with squeezed states and homodyne measurements

Marie Ioannou·Bradley Longstaff·Mikkel V. Larsen·Jonas S. Neergaard-Nielsen·Ulrik L. Andersen·Daniel Cavalcanti·Nicolas Brunner·Jonatan Bohr Brask
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Abstract

We present a scheme for quantum randomness certification based on quantum steering. The protocol is one-sided device independent, providing high security, but requires only states and measurements that are simple to realise on quantum optics platforms - entangled squeezed vacuum states and homodyne detection. This ease of implementation is demonstrated by certifying randomness in existing experimental data and implies that giga-hertz random bit rates should be attainable with current technology. Furthermore, the steering-based setting represents the closest to full device independence that can be achieved using purely Gaussian states and measurements.

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Marie Ioannou, Bradley Longstaff, Mikkel V. Larsen, Jonas S. Neergaard-Nielsen, Ulrik L. Andersen, Daniel Cavalcanti, Nicolas Brunner, Jonatan Bohr Brask. 2021-11-11. Steering-based randomness certification with squeezed states and homodyne measurements. https://doi.org/10.1103/physreva.106.042414

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