Magnon Quantum Computing Gets a 100x Lifetime Boost

Quantum computers are large, fragile, and costly. The superconducting systems from Google and IBM fill whole rooms with their cooling equipment. Trapped-ion machines require high-vacuum chambers and many precise lasers. Recently, researchers at the University of Vienna introduced a new idea: magnon quantum computing. Here, quantum information travels through collective spin waves in a magnetic crystal that can be as small as a pinhead.

The researchers made magnons last almost 100 times longer, reaching coherence times of up to 18 microseconds. This puts magnons on par with superconducting qubits. Their results were published in Science Advances in May 2026 and received a lot of attention in June. The takeaway is surprising: if magnons can handle quantum information as well as superconducting circuits, quantum computers could go from filling rooms to fitting on a coin.

What are magnons?

A magnon is a quasiparticle, which means you can't actually hold one. It represents a group movement of electron spins inside a magnetic material. Imagine a stadium where fans do a Mexican wave - the people stay put, but the wave travels around. In a crystal lattice, a magnon is the smallest possible unit of that wave's energy.

Magnons operate at gigahertz frequencies and have wavelengths measured in nanometres. This matters because it matches the range used by standard microwave electronics. Unlike photons in optical quantum computing, which require bigger parts, magnon devices could be built at the nanoscale. This makes magnon quantum computing exciting, since the hardware could be very small.

Up to now, the biggest problem was that magnons disappeared too quickly. In most magnetic materials, a magnon only lasts for nanoseconds, which is too short for practical quantum operations. The Vienna team discovered that this short lifetime is not a fundamental law of physics, but actually comes down to the material used.

They used ultra-pure spheres of yttrium iron garnet (YIG), a synthetic crystal known for its very low magnetic losses. The team cooled these spheres to 30 millikelvins, which is just 0.03 degrees above absolute zero, using a rare piece of equipment - only the sixth one like it in the world. At this temperature, thermal noise, or the random movement of atoms that disrupts quantum states, is almost gone. Thanks to the high purity and low temperature, the team achieved magnon coherence times close to 18 microseconds. Earlier attempts had only managed a few hundred nanoseconds.

The key finding was that using shorter-wavelength magnons and very pure material greatly reduced scattering. There is no fundamental law of physics that limits how long a magnon can last. Instead, the magnon's lifetime depends entirely on the quality of the crystal and the conditions it is used in.

No one is building a magnon quantum computer yet. The Vienna team's result is only a proof of concept, not a blueprint for a finished product. But it removes what many believed was a fundamental obstacle. If magnon lifetimes were limited by physics, progress would have stopped. Instead, the limit comes from materials science. That's an engineering challenge, and with enough time and resources, engineering problems are usually solved.