Quantum Random Number Generation Techniques

Quantum random number generators exploit the inherent indeterminism of quantum mechanics to produce sequences of truly unpredictable bits. Unlike classical pseudo-random algorithms, their outputs resist prediction even in principle. Techniques range from measuring vacuum fluctuations in optical fields and phase noise in lasers to photon arrival times and entanglement-based protocols. Device-dependent schemes, which assume well-characterised components, can achieve high throughputs by modelling sources and detectors. Self-testing (device-independent) approaches harness nonlocal correlations to certify randomness without detailed device models, while semi- or source-device-independent methods strike a balance between trust assumptions and performance. Recent advances have yielded integrated photonic implementations, kilometre-scale fibre deployments and remote cloud-accessible setups, underscoring the global relevance of secure random numbers in cryptography, simulations and critical infrastructure. Applications span secure key generation, Monte Carlo simulations, numerical modelling, lottery systems and randomised algorithms. Ongoing research addresses calibration-free measurement, finite-size security, side-channel mitigation and scalability towards gigabit and terabit per second rates. The convergence of foundational protocols and practical engineering is paving the way for widespread adoption of quantum random number generation across communication networks, data centres and consumer devices.

Research from Nature Portfolio

Recent studies have demonstrated certified randomness generation using a remote trapped-ion processor, in which challenge circuits are executed on a multi-qubit device and the resulting output is verified to produce tens of thousands of bits with quantifiable entropy under realistic adversarial models. Another line of work has introduced a homodyne-based protocol that removes the need for device calibration, expediting practical deployment on integrated optics platforms. This system, operating at megahertz rates, incorporates finite-size security analysis and self-testing features, thus offering provably secure randomness expansion suitable for on-chip implementations.

Research from all publishers

One development achieved one-sided device-independent randomness through quantum steering over a two-kilometre fibre link, yielding multi-megabit per second bit streams while tolerating untrusted devices at one end. In parallel, an optoelectronic integrated circuit was custom-codesigned to harness vacuum fluctuations at 100 Gbit/s, setting a new record for secure chip-scale generators and accounting for both classical and quantum side information. Additionally, a semi-device-independent approach based on broadband squeezed light has realised hundreds of megabit per second private bit generation, leveraging a noisy local oscillator and metropolitan-scale transmission of entropy sources for enhanced flexibility in real-world networks.

Quantum Random Number Generation Techniques publication trend

The graph below shows the total number of articles in quantum random number generation techniques across all publications each year (not limited to Nature Index journals).

Technical terms

Vacuum fluctuations: Spontaneous variations in the electromagnetic field inherent to the quantum vacuum, used as an entropy source.

Entanglement: A quantum correlation between particles that enables nonlocal verification of randomness without assuming device trust.

Quantum steering: A type of entanglement-based protocol whereby one party influences the state of a distant system to certify randomness.

Homodyne detection: A measurement technique that interferes a signal with a reference beam to extract continuous-variable quantum information.

Device independence: A security paradigm requiring minimal assumptions about the internal operation of measurement devices.

Randomness expansion: The process of generating more certified random bits than the initial seed by exploiting quantum processes.

References

1. Certified randomness using a trapped-ion quantum processor. Nature (2025).
2. Provably-secure quantum randomness expansion with uncharacterised homodyne detection. Nature Communications (2023).
3. One-sided device-independent random number generation through fiber channels. Light: Science & Applications (2025).
4. 100-Gbit/s Integrated Quantum Random Number Generator Based on Vacuum Fluctuations. PRX Quantum (2023).
5. Semi-device-independent quantum random number generator with a broadband squeezed state of light. npj Quantum Information (2024).