Quantum Elements Surfaces Over Error Code Limitations on IBM Heron Processors

Quantum Elements and the University of Southern California (USC) have published a Nature Communications paper demonstrating that the surface code can improve error protection even on a quantum processor whose physical layout does not naturally match the code.

The researchers used IBM Heron processors, which have a heavy-hex architecture that is not optimized for surface codes. They combined a depth-efficient code with dynamical decoupling to suppress idle-time noise and enabled directional subthreshold scaling.

This breakthrough has important implications for fault-tolerant quantum systems, as it shows that a processor does not need to be designed around the exact geometry of the surface code to receive its benefits. This means that the code can be adapted across a broader range of superconducting architectures.