AI designs quantum circuits that could secure future networks
Researchers have used machine learning to automatically design photonic systems that prove quantum mechanics' spooky predictions work in practice. The breakthrough brings device-independent quantum networks—unhackable communication systems immune to detector fraud—closer to commercial viability by making them easier to build and more resistant to real-world signal loss.
Originaltitel: Automated generation of photonic circuits for Bell tests with homodyne measurements
Nonlocal quantum realizations, certified by the violation of a Bell inequality, are core resources for device-independent quantum information processing. Although proof-of-principle experiments demonstrating device-independent quantum information processing have already been reported, identifying physical platforms that are realistically closer to practical, viable devices remains a significant challenge. In this work, we present an automated framework for designing photonic implementations of nonlocal realizations using homodyne detections and quantum state heralding. Combining deep reinforcement learning and efficient simulations of quantum optical processes, our method generates photonic circuits that achieve significant violations of the Clauser-Horne-Shimony-Holt inequality. In particular, we find an experimental setup, robust to losses, that yields a CHSH violation of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mn>2.068</mml:mn> </mml:math> with <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mn>3.9</mml:mn> </mml:math> dB and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mn>0.008</mml:mn> </mml:math> dB squeezed light sources and two beam splitters.