For decades, magnons have shown enormous promise for quantum technologies, but one critical limitation has kept them from practical use: they disappear almost as soon as they form.

Now, an international team of physicists led by Andrii Chumak at the University of Vienna has increased magnon lifetimes by nearly two orders of magnitude, from just a few hundred nanoseconds to as long as 18 microseconds.

The researchers also discovered that this limit is set not by fundamental physics, but largely by material quality, pointing to a clear path toward even longer-lived magnons. The breakthrough could ultimately help enable highly compact quantum computers, potentially no larger than a 1-cent coin. The findings were published in Science Advances.

Why Magnons Matter
Magnons move through magnetic solids as small waves in magnetization, similar to ripples spreading across water after a stone is dropped into a pond. Unlike photons, which can move through empty space or optical fibers, magnons travel inside solid magnetic materials.

Their wavelengths can shrink to the nanometer scale, meaning magnonic circuits could, in principle, be built on chips no larger than those already used in today’s smartphones. Because a magnon is an excitation inside a solid, it also naturally interacts with many other fundamental quasiparticles, including phonons and photons. That makes magnons promising building blocks for hybrid quantum systems and quantum metrology.