Floquet odd-parity collinear magnets

Abstract: Altermagnets (AMs), recently discovered unconventional magnets distinct from ferro- and antiferromagnets, have rapidly emerged as a prominent frontier in condensed matter physics. AMs are characterized by alternating collinear magnetic moments with zero net magnetization in real space, and spin splittings with even-parity symmetry in momentum space. However, their counterparts exhibiting odd-parity spin splitting remain largely unexplored. Here, based on symmetry argument, we show that such unconventional odd-parity magnets can be induced from collinear antiferromagnets. Remarkably, using effective model analysis within Floquet-theory framework, we demonstrate that circularly polarized light irradiation of conventional antiferromagnetic lattices induces both $p$- and $f$-wave magnets, realizing novel magnetic states dubbed Floquet odd-parity collinear magnets. Moreover, we also uncover light-induced antiferromagnetic Chern insulating states in the $f$-wave magnets. The proposed Floquet odd-parity magnet is confirmed by first-principles calculations of MnPSe$_{3}$ under circularly polarized light. Our work not only proposes a new class of unconventional magnets, but also opens an avenue for light-induced magnetic phenomena in spintronic applications.