Q-CTRL Breaks 100-Qubit Barrier with Quantum Fourier Transform on IBM Hardware

Researchers at Q-CTRL have made significant strides in quantum computing by successfully executing the Quantum Fourier Transform (QFT) on IBM's Heron r3 processor, a 156-qubit device. This achievement marks a major milestone in the development of large-scale quantum algorithms.

The team used a novel compilation strategy called Convolutional QFT, which reduces noise accumulation and improves execution fidelity. By incorporating an ancilla qubit and minimizing entangling gates, they were able to compress the circuit logic into a compact kernel gadget that steps sequentially along the qubit register.

The demonstration achieved remarkable results, with the correct target frequency emerging as the unique mode result in all test circuits up to 100 qubits. The team also observed a significant increase in selectivity and unitary process fidelity at larger register scales.