A team of researchers have published a paper in which they show that a quantum computer can produce certified randomness, which has numerous application areas such as in cryptography.
According to the paper, published in Nature, random-number generation is a natural task to demonstrate quantum computing’s supremacy over traditional, classical computing, as randomness is intrinsic to quantum mechanics.
One of the researchers, Marco Pistoia, head of global technology applied research and a distinguished engineer at JPMorgan Chase, said that applications of certified randomness include cryptography, solving complex mathematical problems, and fairness and privacy.
The paper in Nature notes that the main challenge for any application or device that needs to receive randomness from a third-party provider, such as a hardware security module, is that it needs to verify that the bits received are truly random and freshly generated.
The team of researchers from JPMorganChase, Quantinuum, Argonne National Laboratory, Oak Ridge National Laboratory, and the University of Texas at Austin used a technique known as Random Circuit Sampling (RCS). RCS is used to perform a certified-randomness-expansion protocol, which outputs more randomness than it takes as input. It is a task that is often used to demonstrate quantum supremacy since it cannot be achieved on a classical computer.
Scott Aaronson, Schlumberger centennial chair of computer science and director of the Quantum Information Center at The University of Texas at Austin, said: “When I first proposed my certified randomness protocol in 2018, I had no idea how long I’d need to wait to see an experimental demonstration of it.”
Using a 56-qubit Quantinuum System Model H2 trapped-ion quantum computer, the researchers demonstrated that a quantum computer can now achieve computational power beyond that offered by the most powerful classical supercomputers. Accessing H2 remotely over the internet, the team generated certifiably random bits.
The randomness was checked using Frontier, Summit, Perlmutter and Polaris supercomputers equipped with graphics processing units (GPUs), which are especially suitable for quantum circuit simulations. With a combined sustained performance of 1.1 ExaFLOPS from the supercomputers, the team certified 71,313 bits of entropy, a measure of randomness.
Discussing the breakthrough, Aaronson said: “This is a first step toward using quantum computers to generate certified random bits for actual cryptographic applications.”
Pistoia added: “This work marks a major milestone in quantum computing, demonstrating a solution to a real-world challenge using a quantum computer beyond the capabilities of classical supercomputers today.”
Rajeeb Hazra, president and CEO of Quantinuum, said: “Our application of certified quantum randomness sets a new standard for delivering robust quantum security and enabling advanced simulations across industries like finance, manufacturing and beyond.”
Travis Humble, director of the Quantum Computing User Program, and director of the Quantum Science Center, both at Oak Ridge National Laboratory, added: “These results in quantum computing were enabled by the world-leading US Department of Energy computing facilities at Oak Ridge National Laboratory, Argonne National Laboratory and Lawrence Berkeley National Laboratory. Such pioneering efforts push the frontiers of computing and provide valuable insights into the intersection of quantum computing and high-performance computing.”
