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arXiv · 2410.11685

Polarization-encoded photonic quantum-to-quantum Bernoulli factory based on a quantum dot source

Giovanni Rodari·Francesco Hoch·Alessia Suprano·Taira Giordani·Elena Negro·Gonzalo Carvacho·Nicolò Spagnolo·Ernesto F. Galvão·Fabio Sciarrino
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Abstract

A Bernoulli factory is a randomness manipulation routine that takes as input a Bernoulli random variable, outputting another Bernoulli variable whose bias is a function of the input bias. Recently proposed quantum-to-quantum Bernoulli factory schemes encode both input and output variables in qubit amplitudes. This primitive could be used as a sub-routine for more complex quantum algorithms involving Bayesian inference and Monte Carlo methods. Here, we report an experimental implementation of a polarization-encoded photonic quantum-to-quantum Bernoulli factory. We present and test three interferometric set-ups implementing the basic operations of an algebraic field (inversion, multiplication, and addition) which, chained together, allow for the implementation of a generic quantum-to-quantum Bernoulli factory. These in-bulk schemes are validated using a quantum dot-based single-photon source featuring high brightness and indistinguishability, paired with a time-to-spatial demultiplexing setup to prepare input resources of up to three single-photon states.

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Giovanni Rodari, Francesco Hoch, Alessia Suprano, Taira Giordani, Elena Negro, Gonzalo Carvacho, Nicolò Spagnolo, Ernesto F. Galvão, Fabio Sciarrino. 2024-10-15. Polarization-encoded photonic quantum-to-quantum Bernoulli factory based on a quantum dot source. https://doi.org/10.1126/sciadv.ado6244

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