All-optical quantum random bit generation from intrinsically binary phase of parametric oscillators.

Area of Science:

• Quantum Optics
• Photonics
• Quantum Information Science

Background:

• Quantum random number generators (QRNGs) are crucial for secure communication and computation.
• Existing QRNGs often rely on photodetection and post-processing, limiting speed and integration.
• All-optical approaches offer potential for faster, more robust QRNGs.

Purpose of the Study:

• To demonstrate a novel all-optical quantum random number generator (RNG).
• To investigate the use of a degenerate optical parametric oscillator (OPO) for RNG applications.
• To confirm the quantum origin of randomness and eliminate classical noise contributions.

Main Methods:

• Utilized an above-threshold binary phase state selection in a degenerate optical parametric oscillator (OPO).
• Leveraged spontaneous parametric down-conversion (SPDC) for photon generation.
• Analyzed the generated bit sequence for statistical randomness without photodetection or post-processing.

Main Results:

• Demonstrated an all-optical quantum RNG with statistically random output at 99% confidence.
• Verified that randomness originates from the quantum phase of initiating photons from SPDC.
• Showed negligible contribution from classical noise sources to the random bit generation.

Conclusions:

• The developed all-optical OPO-based RNG is a promising technology for secure applications.
• The technique enables simple, robust, and high-speed on-chip quantum RNGs.
• Micro- and nanoscale OPO resonators can further enhance the performance and miniaturization of these devices.