Search arXiv⌕ Search
Home/Archive/arXiv

arXiv · 2511.13136

Topological phase transitions by time-dependent electromagnetic fields in frustrated magnets: Role of dynamical and static magnetic fields

Tatsuya Shirato·Ryota Yambe·Satoru Hayami
View original source ↗Read source document ↗Export metadata ↓

Abstract

We theoretically investigate the effects of time-dependent electromagnetic fields on frustrated magnets with the spatial inversion symmetry. Two types of external-field setups are considered: One is a circularly polarized electromagnetic field and the other is a combination of a circularly polarized electric field and a static magnetic field. The system is modeled by a classical frustrated Heisenberg model on a triangular lattice, whose ground state is a single-$Q$ spiral spin configuration. The effects of irradiated electric and magnetic fields are taken into account by the inverse Dzyaloshinskii-Moriya (DM) interaction and the Zeeman coupling, respectively, without heating effects. By numerically solving the Landau-Lifshitz-Gilbert equation, we find that the two field configurations lead to distinct skyrmion crystal (SkX) phases and their associated topological phase transitions: in the former setup, SkXs composed of skyrmions with skyrmion numbers of one and two with opposite signs emerge, whereas in the latter setup, SkXs with the same sign appear. The stabilization mechanisms of these SkXs are accounted for by the competition among electromagnetic-field-induced chiral DM interactions, electric-field-induced three-spin interactions, and the Zeeman coupling based on the high-frequency expansion within the Floquet formalism. Furthermore, for the latter setup, we find that the stability region of the SkX phase varies significantly depending on the timing of the application of the circularly polarized electric field and the static magnetic field. Our findings would broaden the possible routes to generate and control SkXs by time-dependent electromagnetic fields, advancing both the theoretical comprehension and experimental control of topological spin crystals.

Explore related subjects

cond-mat.str-el

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Tatsuya Shirato, Ryota Yambe, Satoru Hayami. 2025-11-17. Topological phase transitions by time-dependent electromagnetic fields in frustrated magnets: Role of dynamical and static magnetic fields. https://doi.org/10.1103/mt2j-r57h

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2026

Exotic Spin Excitation Continuum in a Weakly Coupled Quantum Chainsaw Antiferromagnet

Collective motions in strongly interacting magnets involve many spins and are often described in terms of integer-spin excitations. However, in certain cases, the collective motion can behave as if these integer excitations break apart into smaller, particle-like entities with unusual properties. Such fractionalized excitations in quantum magnets are commonly associated either with topological order in two dimensions or with criticality in one dimension. It remains unclear how these distinct mechanisms are connected across a dimensional crossover. Here we investigate the Ti-based quantum antiferromagnet, $Cs_{8}LiNa_{3}Ti_{12}F_{48}$, in which $Ti^{3+}$ ($3d^{1}$, $S=1/2$) ions interact antiferromagnetically within distorted kagome planes. Our inelastic neutron scattering study on a single crystal reveals a frustrated network of weakly coupled spin-$1/2$ chainsaws, realizing a regime of dimensional frustration in which interchain couplings fail to establish coherent two-dimensional order. The magnetic excitation spectrum exhibits a strong continuum spanning the full measured momentum and energy phase space. In addition, the dynamic spin correlation function displays rod-like scattering in momentum space, indicating a quasi-one-dimensional nature of the magnetic correlations. These results point to fractionalized excitations with intrinsically directional character, demonstrating that signatures of one-dimensional criticality can persist within a two-dimensional lattice. Our findings establish anisotropic fractionalization as a distinct organizing principle for quantum-disordered states.

cond-mat.str-el↗
arXiv2026

Quantum-interference-driven orbital density wave and high-temperature superconductivity in trilayer nickelates

Intertwined charge-density-wave (CDW) and spin-density-wave (SDW) orders are a hallmark of high-temperature superconducting multilayer nickelates. In trilayer La4Ni3O_{10}, charge correlations develop at temperatures above the onset of long-range spin order, and the characteristic ordering wavevectors satisfy $Q_{cdw} \approx 2Q_{sdw}$. Here, using a density-wave equation with vertex corrections, we show that quantum interference between short-range SDW fluctuations at $q \approx Q_{sdw}$ on the outer NiO2 layers generates an inter-outer-layer bond order at $Q_{cdw} \approx 2 Q_{sdw}$. This bond order induces a pronounced inner-layer-centered orbital order, with antiphase modulations of the Ni $d_{3z^2-r^2}$ and $d_{x^2-y^2}$ occupations, producing strong orbital polarization but only weak total charge modulation. This intertwined bond-and-orbital order accounts for the layer-selective electronic reconstruction inferred from NMR/NQR and is consistent with Raman spectroscopy and scanning tunnelling microscopy measurements. The same orbital and spin fluctuations also cooperate to stabilize $s_{\pm}$-wave superconductivity through $M_z$ mirror-parity selection rules. Our results provide a unified microscopic framework for intertwined density-wave order and high-Tc superconductivity in multilayer nickelates.

cond-mat.str-el↗
arXiv2026

Model Fractional Quantum Hall States on Lattices: Exact Parent Hamiltonians and Routes to Realization

Recent advances in engineered quantum platforms have enabled the realization of bosonic Laughlin states at $ν=1/2$ and brought non-Abelian topological phases within experimental reach. A central theoretical challenge is to develop a unified framework connecting lattice fractional quantum Hall (FQH) model states, exact parent Hamiltonians, and experimentally accessible interactions. We systematically construct Hermitian parent Hamiltonians for which continuum lowest Landau level (LLL) model states sampled on lattice sites are exact zero modes. Using these model manifolds as quantitative references, we find that, within the projected lattice LLL at the flux densities studied, short-range density interactions stabilize Laughlin ground-state manifolds at $ν=1/3$ and $1/4$, while two-body onsite repulsion supports a Moore--Read triplet at $ν=1$. Full multiband calculations reveal a sharp contrast: the Laughlin manifolds remain robust against interband mixing on the studied tori, whereas the Moore--Read triplet becomes less spectrally isolated and eventually undergoes a level crossing with competing states near the interband scale. Our framework provides a theoretical foundation for using lattice model states to guide the search for experimentally accessible Abelian and non-Abelian FQH states.

cond-mat.str-el↗