Useful quantum computers will depend on logical qubits, which are constructed from multiple physical qubits to shield information from errors. Because quantum states are fragile, error correction has been a major hurdle in the field.
Researchers have now set a new record for how reliably these logical qubits can operate. The improvement over earlier efforts brings error-corrected quantum computing closer to practical use, though the source notes that many logical qubits will still be needed for real-world applications.
The result is a significant milestone, but it is not the finish line. Building a useful quantum computer will require scaling up this reliability across many logical qubits working together, and that challenge remains ahead.