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arXiv · 2511.05672

Semi-device-independent randomness certification on discretized continuous-variable platforms

Moisés Alves·Vitor L. Sena·Santiago Zamora·Tailan S. Sarubi·A. de Oliveira Junior·Alexandre B. Tacla·Rafael Chaves
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Abstract

Randomness is fundamental for secure communication and information processing. While continuous-variable optical systems offer an attractive platform for this task, certifying genuine quantum randomness in such setups remains challenging. We present a semi-device-independent scheme for randomness certification tailored to continuous-variable implementations, where the dimension assumption is operationally implemented by restricting state preparations to the two-level Fock subspace. Using standard homodyne and displacement-based measurements, we show that simple optical setups can achieve dimension-witness violations that certify positive min-entropy, even in the presence of realistic losses and misaligned reference frames. These results demonstrate that practical and scalable quantum randomness generation is achievable with minimal experimental complexity on continuous-variable platforms.

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Moisés Alves, Vitor L. Sena, Santiago Zamora, Tailan S. Sarubi, A. de Oliveira Junior, Alexandre B. Tacla, Rafael Chaves. 2025-11-07. Semi-device-independent randomness certification on discretized continuous-variable platforms. https://doi.org/10.1103/z3s5-bhb7

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