A quantum computer is like an orchestra where every musician must come in at exactly the right moment. Previously, to play a complex piece, you had to constantly move the instruments around — slow and noisy. The new scheme, called "parity architecture," keeps everyone in place, and the conductor simply changes the notes.
On the IBM Heron r3 chip with 50 qubits, this scheme demonstrated an accuracy of about 1%—the best result for its size. The main win is in speed: instead of swaps between qubits, it uses their natural interactions. The speedup grows super-exponentially, meaning faster than any power law.
If you add the iSWAP gate to the instruction set, which swaps the states of two qubits in a single step, the scheme becomes even faster. It's like allowing the orchestra to play two notes at once instead of sequentially. This approach paves the way for larger and more precise quantum computations.
Super-exponential growth means that when you double the number of qubits, the speedup is squared, not just doubled.