Quantum Random Number Generators (QRNGs)

News: Indian researchers at RRI, used a general-purpose quantum computer to certify true random numbers, making real-life deployment feasible and strengthening digital security.

About Quantum Random Number Generators (QRNGs)

• QRNGs use quantum phenomena to generate truly random numbers for secure cryptographic keys and critical security applications.
• Working Mechanism
  • QRNGs tap the built-in uncertainty of quantum mechanics to provide a genuinely unpredictable source of randomness.
  • They use a quantum entropy source—such as photon arrival times—where each detection is an independent, random event.
  • A photon-based source is used, where single photons pass through a beam splitter so that each path choice is intrinsically unpredictable.
  • Detectors then record the outcomes and convert them into bits, creating a binary stream that reflects this inherent uncertainty.
  • The bitstream is checked with stringent statistical tests to verify unpredictability and remove any bias introduced by the setup.
  • By confirming that the numbers arise from quantum behavior rather than device artifacts, this method delivers authentic randomness, clearly setting QRNGs apart from classical generators.
• Significance: Certified true randomness can enable hack-proof digital security and strengthen the foundations of modern encryption systems.
• Use of QRNGs
  • Create robust encryption keys and improve secure communications and cryptographic protocols.
  • Protect passwords and authentication systems against prediction and pattern-based attacks.
  • Support scientific research, simulations, and modeling that require high-quality random inputs.
  • Enhance security architectures in noisy, real-world environments.
• India’s Contributions
  • Institution involved: This work was led by the team of physicists at the Raman Research Institute, Bengaluru.
  • Indian researchers advanced certified quantum randomness by addressing the device-certification problem and demonstrating techniques to generate truly random numbers.
  • Earlier experiments worldwide relied on entanglement tests that violated Bell’s Inequality, which typically required large spatial separation and were impractical for deployment.
  • Adopting a different approach, the Indian team used time separation in a single particle and showed loophole-free violations of the Leggett–Garg inequality (LGI) to certify intrinsic randomness.
  • They then validated this certified-randomness method on a commercially available general-purpose quantum computer for real-world conditions.