Quantum magnonics aims to harness magnon properties for nanoscale quantum information technologies, but substrate-induced damping in yttrium iron garnet (YIG) films limits low-temperature performance. Here, the authors demonstrate that YIG films on yttrium scandium gallium aluminum garnet substrates maintain low magnetic damping from room temperature to millikelvin levels, eliminating paramagnetic substrate effects and advancing spin-wave-based quantum technologies.
- Rostyslav O. Serha
- Carsten Dubs
- Andrii V. Chumak