Researchers at the California Institute of Technology suggest that a practical quantum computer may need far fewer qubits than previously believed, potentially making deployment possible before the end of the decade.
In collaboration with Caltech-affiliated startup Oratomic, the team found that by reducing the errors that currently limit early-stage quantum systems, a functional machine could be built with roughly 10,000 to 20,000 qubits.
Earlier estimates had placed that requirement in the millions. A qubit—the quantum equivalent of a classical bit—serves as the basic unit of information in quantum computing.
According to the researchers, needing fewer qubits significantly shortens the timeline, meaning quantum computers could, in theory, become operational by around 2030.
The breakthrough centers on a new error-correction approach using neutral-atom systems, where atoms are manipulated and linked across distances with laser-based “optical tweezers.”
“We are developing new architectures for neutral-atom quantum processors that dramatically reduce the resource estimates for fault-tolerant quantum computing,” said Caltech theoretical physicist John Preskill.
“This progress makes me optimistic that broadly useful quantum computing will soon be a reality.”
Manuel Endres, a professor of physics at Caltech who recently created the largest qubit array ever assembled, said:
“Unlike other quantum computing platforms, neutral atom qubits can be directly connected over large distances. Optical tweezers can shuttle one atom to the other end of the array and directly entangle it with another atom.”
Caltech said the new approach allows each logical qubit to be encoded using as few as five physical qubits, compared to roughly a thousand required by conventional methods.
“It’s actually very surprising how well this works,” Endres said. “It’s what we call ultra-efficient error correction.”
Quantum Frontiers Closer Than Expected
Oratomic said it will collaborate closely with Caltech’s Advanced Quantum Computing Mission, continuing research into quantum information processing with the aim of building the world’s first utility-scale, fault-tolerant quantum computer.
The announcement comes a day after Google published a paper suggesting that quantum computers could potentially break Bitcoin’s cryptography in just nine minutes, requiring far less computing power than previously estimated.
In the paper, Google urged crypto developers to begin transitioning blockchains to post-quantum cryptography (PQC) now, rather than waiting for real-world threats to materialize.
Last week, the company set a 2029 target for its PQC migration, cautioning that the “quantum frontiers” may be closer than they seem.
