Quantum random number generation based on spontaneous Raman scattering in standard single-mode fiber

Area of Science:

• Quantum physics
• Photonics
• Information security

Background:

• Quantum random number generation (QRNG) is crucial for secure communication.
• Traditional QRNG methods often rely on single entropy sources, limiting efficiency.
• Spontaneous Raman scattering in optical fibers offers a novel platform for QRNG.

Purpose of the Study:

• To investigate quantum random number generation utilizing backward spontaneous Raman scattering.
• To leverage both photon wavelength and arrival time as independent entropy sources.
• To achieve high-quality random bit generation with optimal rates.

Main Methods:

• Utilizing backward spontaneous Raman scattering in standard single-mode fiber.
• Employing four avalanche photodiodes in gated Geiger mode for photon detection across different wavelength channels.
• Using a time-to-digital converter to record photon arrival times.
• Combining wavelength and arrival time information for random bit generation.
• Applying SHA-256 hashing for post-processing to remove bias.

Main Results:

• Achieved generation of five-bit raw data per effective click with 2.87-bit min-entropy.
• Optimized pump power and fiber length for efficient random bit generation rates.
• Successfully passed the NIST statistical test suite for the generated random bit sequences.

Conclusions:

• Demonstrated a robust QRNG system based on backward Raman scattering.
• Validated the effectiveness of combining dual entropy sources (wavelength and arrival time).
• The proposed method offers a promising approach for high-performance quantum random number generation.