(ZDNet) IBM is launching a new quantum speed metric, in a move that is likely to add a dose of competitiveness across an industry that is growing at pace.
Named CLOPS (Circuit Layer Operations Per Second), the metric is the first to measure the number of quantum circuits a quantum processing unit (QPU) can execute per unit of time, and is designed to provide an objective understanding of the amount of work a quantum system can do in a particular period.
Speed is only one of the three critical attributes that reflect the performance of a quantum computer, according to IBM, with the two others being scale and quality. Scale is measured by the number of qubits that the quantum processor supports, while quality can be determined thanks to quantum volume, which is another benchmark that IBM developed in 2017 to gauge how faithfully a quantum circuit can be implemented in a quantum computing system.
“Without progress on all three, we will not have practical and useful quantum computing systems,” Bob Sutor, chief quantum exponent at IBM, tells ZDNet. “Would you want a slow, poor quality, but big machine? How about a high-quality system that does not have enough qubits to tackle your problem? Would you use a system that was hundreds of times slower than a competitor’s system?”
CLOPS measures the speed of quantum circuits, which are the basic unit of computation for quantum computers, and which include the sequence of quantum operations, but also the interaction of the quantum system with a classical computer.
IBM has run CLOPS to benchmark several of the company’s quantum processors, ranging from five-qubit systems to 65-qubit devices. Although all of the quantum computers had a similar quantum volume, IBM’s researchers found vast differences in speed: the largest machine performed the slowest, at a CLOPS of 753 layers per second, compared to 1,419 for the smallest processor.
The company hopes, therefore, that CLOPS will provide a wider-ranging understanding of the performance of quantum hardware, which is not limited to the number of qubits or to quantum volume alone. “The three quantum performance metrics allow quantum computing providers to share the true performance of their systems to the world,” says Sutor.