A team of researchers spanning the banking, technology, and academic sectors has claimed a major advance in quantum security infrastructure. In a peer-reviewed paper published on 5 June in PRX Quantum, the group reported what they describe as the world’s first fully integrated, self-testing quantum random number generator (QRNG) on a silicon photonic chip, branded QDice®.
The paper, titled “Self-testing quantum randomness expansion on an integrated photonic chip”, addresses what the authors call a critical vulnerability in digital security: the difficulty of verifying whether random number generators remain secure as hardware components age or drift. Random numbers underpin encryption across financial transactions, cloud services, and communications, but current systems require users to trust that devices remain reliable over time—a guarantee researchers say cannot be assured.
According to the team, QDice® uses a measurement-device-independent protocol that treats internal components as “black boxes.” The system continuously tests its measurement devices, producing certified random bits only when a threshold score is met. If the score falls short, the process aborts, which the researchers argue ensures security.
Dr Ng Hong Jie, Senior Software Engineer at Squareroot8 Technologies, said: “QDice® sits in a very sweet spot between the security versus practicality trade-off, making it one of the most secure QRNGs that are commercially available in the market.”
The chip was fabricated at Singapore’s Advanced Micro Foundry and reportedly operates at room temperature without cryogenic cooling. The team emphasized that it uses standard semiconductor processes, making large-scale production feasible.
The researchers asserted that QDice® offers a level of protection unmatched by classical devices, since its security framework assumes even potential quantum correlations with the chip could be exploited by attackers. However, they acknowledged a trade-off: while typical QRNGs can reach speeds above 100 gigabits per second, QDice® currently produces random numbers at 64 bits per second. The team said they are working on improving detector efficiency, which they claim could raise speeds to 68 megabits per second.
Dr Goh Koon Tong, Co-Founder and Chief Technologist at Squareroot8 Technologies, stated: “What we have done here is turn quantum light into verifiably secure random numbers with the entirety of the process within a single chip smaller than the size of your fingernail. This will undoubtedly be a major step towards mass adoption of quantum technologies.”
The researchers argued that the inability to continuously verify randomness is a structural vulnerability across sectors including finance, government, healthcare, and AI. They claim QDice® is the first production-ready chip to close this gap, with potential applications ranging from data centres to Internet of Things devices.
The project was conducted by a cross-industry team from the following organisations:
- Department of Electrical & Computer Engineering, National University of Singapore, Singapore
- State Key Laboratory of Extreme Photonics and Instrumentation, Zhejiang Key Laboratory of Optoelectronic Information Technology, College of Optical Science and Engineering, Zhejiang University, Hangzhou, China
- Squareroot8 Technologies Pte Ltd, Singapore
- Centre for Quantum Technologies, National University of Singapore, Singapore
- Global Technology Applied Research, JPMorganChase, New York, New York 10017, USA
- IonQ, College Park, Maryland 20740, USA
- IonQ Italia, Rome, RM, Italy
While the claims have been peer-reviewed, independent experts will likely scrutinize the practical performance and scalability of QDice® as the technology moves toward commercialization.
Published paper: https://journals.aps.org/prxquantum/abstract/10.1103/h7kt-m5fc
