We declare the observation of spin superfluid state in Yttrium Iron Garnet (YIG) at room temperature. It is similar to a Homogeneous Precessing State (HPD), observed earlier in antiferromagnetic superfluid 3He-B. The formation of this state explains by the repulsive interaction between magnons, which is required as a prior condition for the spin superfluidity. It establishes an energy gap, which stabilizes the long range superfluid transport of magnetization and determines the Ginzburg-Landau coherence length. This discovery paves a way to many quantum applications of supermagnonics at room temperature, such as magnetic Josephson effect, long distance spin transport, Q-bit, quantum logics, magnetic sensors and others.
@article{arxiv.1911.03708,
title = {The magnonic superfluid droplet at room temperature},
author = {Yu. M. Bunkov and A. Farhutdinov A. N. Kuzmichev and T. R. Safin and P. M. Vetoshko and V. I. Belotelov M. S. Tagirov},
journal= {arXiv preprint arXiv:1911.03708},
year = {2019}
}