In [I. Luk’yanchuk, Y. Tikhonov, A. Razumnaya, V.M. Vinokur "Hopfions emerge in ferroelectrics", arXiv:1907.03866v1, Nat. Commun. 11, 2433 (2020) ref] the stability of the Hopf fibration-like texture was demonstrated in numerics for the spherical nanoparticle made of the ferroelectric material.
It is interesting to figure out whether the canonical hopfion (particlelike compact formation able to move inside the media in all three dimensions) is possible or not in such materials.
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