Quantum Computers Take Major Leap Toward Real-World Use

Quantum computers have been stuck in the lab for years because their building blocks, called qubits, are incredibly fragile and prone to errors during calculations. A team at ETH Zurich just demonstrated a clever technique that fixes errors while performing complex operations, a breakthrough that brings practical quantum computing significantly closer to reality.

The challenge has always been that quantum computers can protect their qubits when storing information, but the moment you try to use them for actual calculations, everything falls apart. It's like trying to build a house during an earthquake while also repairing the foundation.

Professor Andreas Wallraff and his team, working with researchers from the Paul Scherrer Institute and RWTH Aachen University, found a solution using something called lattice surgery. They started with one protected qubit made of seventeen physical qubits arranged in a square pattern, then carefully split it into two entangled qubits while continuously monitoring and correcting errors every 1.66 microseconds.

The trick works because quantum errors come in two flavors: bit flips, where a qubit switches between 0 and 1, and phase flips, where the quantum state reverses. Classical computers can simply copy information to catch errors, but quantum information cannot be copied due to the laws of physics.

Instead, the team used surface codes, spreading information across multiple physical qubits with special monitoring qubits that watch for errors without disturbing the actual data. During their lattice surgery operation, they kept fixing bit flip errors even while splitting the qubit, something that had never been done successfully before.

Dr. Ilya Besedin, co-leading author of the study published in Nature Physics, explains that superconducting quantum processors face an extra constraint: the qubits are fixed in place. Only neighboring qubits can interact, which makes performing operations between distant qubits extremely difficult.

The Ripple Effect

This advance matters far beyond the lab. Quantum computers promise to revolutionize materials science, drug discovery, and cryptography, but only if they can run long calculations without crumbling under their own errors. By demonstrating fault-tolerant operations between logical qubits, the team showed that scaling up to truly powerful quantum machines is achievable.

The research represents years of work bringing together experimental physicists and theoretical computer scientists. Their success proves that the protective techniques needed for practical quantum computing can work in real hardware, not just on paper.

Every major technology revolution, from transistors to the internet, required solving seemingly impossible engineering challenges. This breakthrough tackles one of quantum computing's most stubborn obstacles, moving the field from "someday maybe" to "probably soon."