A quantum computer has produced a striking result in the race to demonstrate quantum advantage: IBM’s 120-qubit Nighthawk r2 generated one million random-circuit samples in just 19 seconds, while researchers estimate that reproducing the same task with a leading classical supercomputer could require roughly 110 years.
The experiment, led by researchers including Tigran Sedrakyan, used 61 qubits on IBM’s commercially accessible Nighthawk r2 processor. The team ran random quantum circuits reaching 40 cycles and identified a particularly difficult regime at 36 cycles, involving 918 two-qubit gates.
Why the 19-Second Result Matters
The benchmark is known as random-circuit sampling (RCS). It deliberately creates highly complex quantum states that become increasingly difficult for classical computers to reproduce.
Researchers estimated that generating the million-sample dataset would involve about 1.2 × 10²⁷ computational operations under their classical simulation methodology. Using estimates based on the Frontier exascale supercomputer, they arrived at the roughly 110-year comparison.
But the headline needs an important qualification: 110 years is not a permanent limit for classical computing. Better algorithms or simulation techniques could substantially reduce the classical cost. The result therefore demonstrates an advantage under a particular benchmark and computational model—not that classical computers have been permanently defeated.
Nighthawk r2 Is Built for Speed
IBM’s latest Nighthawk r2 has 120 programmable qubits and uses a square-lattice architecture with higher connectivity. Its independent high-speed reset system allows it to execute more than 100,000 circuits per second, with IBM reporting up to a 25× throughput improvement over its Heron systems.
That speed is increasingly important as quantum researchers move beyond simply increasing qubit counts. Error rates, connectivity, circuit depth and how quickly a processor can repeatedly execute useful workloads are becoming equally important measures of progress.
The Bigger Quantum Race
The development comes amid a broader push toward useful, verifiable quantum computing. IBM reported earlier this year that researchers had demonstrated quantum advantage with methods designed to provide greater confidence in results that are difficult to verify classically.
The new Nighthawk experiment is also notable because it used commercially accessible hardware and IBM’s standard cloud execution stack, rather than a one-off experimental machine.
The milestone does not mean quantum computers are ready to replace supercomputers. Instead, it marks another important step in a rapidly evolving contest: finding computational problems where quantum machines can deliver capabilities that classical systems cannot efficiently match.
