The researchers connected Claude to an independent evaluator that checked each design and computed two numbers: how many Toffoli gates it needs and how many logical qubits. Claude took the feedback and improved its designs. In the eighth building block, Claude found a new approach to modular inversion, an operation central to elliptic-curve calculations: in a full point-addition benchmark, one design needed about 17 times fewer gates than the prior design that used the fewest qubits, at the cost of about 12% more qubits. That search took 53 hours.
The researchers stress that these are resource estimates for individual building blocks, not runs on hardware, and that an improvement in the combined metric (gates times qubits) is not a speedup of the same size. The effect on complete applications depends on how the components are used. The study was posted as a preprint on arXiv and was led by Andi Gu as part of Anthropic's STEM Fellows program, with Mikhail Lukin of Harvard and QuEra.
The work builds on an earlier QuEra–Anthropic pilot in which Claude wrote control software for stabilizing lasers in QuEra's quantum computer, which recovered the correct laser lock in 695 of 700 trials, in seconds rather than the 5–10 minutes a human expert needs. QuEra aims to make its Libra computer available on Amazon Braket in 2028.