arXiv subjects

Jin Matsuda

Publications and source records attributed to Jin Matsuda.

3 recordsLinked to original sources

arXiv2026

Parity and time-reversal invariant Ising spin ordering

The interplay of antiferromagnetic order, momentum-dependent Bloch spin-splitting, time-reversal (T), and parity (P) symmetries in non-relativistic systems has emerged as a central theme for spintronics. Two well-known examples are P-preserving and T-violating altermagnets and P-violating and T-preserving odd-parity magnets. These both exhibit an Ising, or uniaxial, Bloch spin-splitting. Here we introduce a new class of coplanar AFMs that generate a P and T symmetric, translation-invariant Ising spin order in real space. Naively, such AFMs are not expected to exhibit unusual phenomena. Here we show that the spin-rotational symmetry breaking generated by these AFMs allows: pure non-relativistic longitudinal (or transverse) spin-conductivities, the generation of non-relativistic altermagnetic spin-splittings through circularly polarized light, and the generation of non-relativistic odd-parity spin-splittings through parity symmetry breaking, by, for example, applied electric fields. We identify 16 candidate materials in the Magndata database for which our theory applies and provide effective microscopic models and DFT-based results that highlight the large emergent responses.

cond-mat.str-el↗

arXiv2026

Ferroaxial magnets: time-reversal-even mirror symmetry violation from spin order

We investigate ferroaxial magnets, a new class of spin-order-driven multiferroic magnets in which magnetic ordering induces mirror-symmetry breaking while preserving both time-reversal and spatial-inversion symmetries. These systems exhibit a ferromagnet-like axial anisotropy that allows optical control of the ferroaxial polarization, while their macroscopic time-reversal symmetry makes them attractive for antiferromagnetic spintronics. Using spin crystallographic group analysis, we identify the candidate materials and the nonrelativistic ferroaxial nature stemming from the strong exchange splitting of magnets. Furthermore, a symmetry-based identification shows magnetic materials that host ferroaxial order and metallic conductivity, realizing the ferroaxial metal state that undergoes a ferroaxial phase transition while remaining metallic. As a direct probe for the ferroaxial metal, we propose a third-order nonlinear Hall effect originating from the transverse coupling between the electric field and Berry curvature dipole mediated by the ferroaxial anisotropy. Our results establish ferroaxial magnets as a platform for nonrelativistic multiferroicity and spintronic applications.

cond-mat.mtrl-sci↗

arXiv2024

Multiferroic collinear antiferromagnet with hidden altermagnetic split

Altermagnets exhibit nonrelativistic spin splitting due to the breaking of time-reversal symmetry and have been garnering significant attention as promising materials for spintronic applications. In contrast, conventional antiferromagnets without spin splitting seem not to have any symmetry breaking and have drawn less attention. However, we show that conventional antiferromagnets with a nonzero propagation vector (Q vector) bring about nontrivial symmetry breakings. The incompatibility between the Q vector and nonsymmorphic symmetry leads to macroscopic symmetry breaking without lifting spin degeneracy. Moreover, the hidden altermagnetic spin splitting in the electronic structure gives rise to various emergent responses. To examine our prediction, we perform first-principles calculations for MnS2 and investigate its multiferroic properties, such as nonlinear transport and optical activity. Our findings reveal unique properties in conventional antiferromagnets, providing another perspective for designing spintronic materials.

cond-mat.mtrl-sci↗