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We find closed-form solution of the Euler equation for a chiral magnet in terms of a skyrmion or a meron depending on the relative strengths of magnetic anisotropy and magnetic field. We show that the relevant length scales for these…

Mesoscale and Nanoscale Physics · Physics 2019-11-27 Sandip Bera , Sudhansu S. Mandal

The ground-state properties of the spin-1/2 antiferromagnetic Heisenberg model with spatially anisotropic couplings on a square lattice are investigated by a spin-rotation-invariant Green's-function approach and by Lanczos diagonalizations…

Strongly Correlated Electrons · Physics 2007-05-23 D. Ihle , C. Schindelin , A. Weisse , H. Fehske

We report on a new source of in-plane anisotropy in nanomagnets due to the presence of Dzyaloshinskii-Moriya interaction (DMI). This anisotropy depends on the shape of the magnet, and is orthogonal to the demagnetization shape anisotropy.…

Mesoscale and Nanoscale Physics · Physics 2016-01-13 M. Cubukcu , J. Sampaio , K. Bouzehouane , D. Apalkov , A. V. Khvalkovskiy , V. Cros , N. Reyren

We propose a geometric framework where dispersion relations are viewed as parametric surfaces in energy-momentum space. Within this picture, the presence and type of critical points of the surface emerge as clear geometric signatures of…

General Relativity and Quantum Cosmology · Physics 2025-10-21 Gines R. Perez Teruel

The zero temperature phase diagram of a one-dimensional S=2 Heisenberg ferromagnet with single-ion cubic anisotropy is studied numerically using the density-matrix renormalization group method. Evidence is found that although the model does…

Condensed Matter · Physics 2009-10-31 M. Dudzinski , G. Fath , J. Sznajd

A computational framework is presented for the sampling of the energy surface of magnetic systems via the systematic identification of first-order saddle points that determine connectivity of metastable states and define the mechanisms of…

Materials Science · Physics 2025-12-09 Hendrik Schrautzer , Tim Drevelow , Hannes Jónsson , Pavel F. Bessarab

The static transverse and longitudinal correlation functions (CF) of a 3-dimensional ferromagnet are calculated for the exactly solvable anisotropic spherical model (ASM) determined as the limit D \to \infty of the classical D-component…

Statistical Mechanics · Physics 2015-06-25 D. A. Garanin

Geometrical frustration and the enhancement of strong quantum fluctuations in two-dimensional triangular antiferromagnets can lead to various intriguing phenomena. Here, we studied the spin-1/2 triangular lattice antiferromagnet…

We study the finite deformation of a thin, elastically heterogeneous sheet subject to electrostatic coupling. The interaction between mechanics and electrostatics is formulated as a saddle-point problem involving the deformation and the…

Analysis of PDEs · Mathematics 2025-12-01 Kateryna Buryachenko , Annegret Glitzky , Matthias Liero , Barbara Zwicknagl

We find a non-perturbative saddle-point solution for the non-linear sigma model proposed by Finkelstein for interacting and disordered electronic systems. Spin rotation symmetry, present in the original saddle point solution, is…

Disordered Systems and Neural Networks · Physics 2009-10-31 Claudio Chamon , Eduardo R. Mucciolo

We put forward a scheme to study the anisotropic magnetic couplings in Sr2IrO4 by mapping fully relativistic constrained noncollinear density functional theory including an on-site Hubbard U correction onto a general spin model Hamiltonian.…

The classical Heisenberg antiferromagnet on a triangular lattice with the single-ion anisotropy of the easy-axis type is theoretically investigated. The mean-field phase diagram in an external magnetic field is constructed. Three…

Strongly Correlated Electrons · Physics 2009-08-24 P. -É. Melchy , M. E. Zhitomirsky

The possibility of a zero temperature, altermagnetic instability in anisotropic two dimensional electron systems in the diffusive regime is analyzed, in the presence and absence of spin-orbit coupling. Allowing for ferromagnetism, a phase…

Strongly Correlated Electrons · Physics 2026-05-08 Alberto Cortijo

We demonstrate that interactions can substantially undermine the free-particle description of magnons in ferromagnets on geometrically frustrated lattices. The anharmonic coupling, facilitated by the Dzyaloshinskii-Moriya interaction, and a…

Strongly Correlated Electrons · Physics 2016-10-28 A. L. Chernyshev , P. A. Maksimov

It is shown that conformal symmetry exists in force-free electrodynamics (FFE) in Minkowski spacetime, a foundational framework for describing magnetospheres around astronomical objects. In force-free magnetospheres, charges are constrained…

General Relativity and Quantum Cosmology · Physics 2026-03-27 Huiquan Li , Jianyong Wang

We present a general formalism for deriving the thermodynamics of ferromagnets consisting of "atoms" carrying an arbitrary irreducible representation of $SU(N)$ and coupled through long-range two-body quadratic interactions. Using this…

High Energy Physics - Theory · Physics 2025-07-08 Alexios P. Polychronakos , Konstantinos Sfetsos

We examine skyrmionic field configurations on a spherical ferromagnet with large normal anisotropy. Exploiting variational concepts of angular momentum we find a new family of localized solutions to the Landau-Lifshitz equation that are…

Mathematical Physics · Physics 2019-10-02 Christof Melcher , Zisis N. Sakellaris

We study a frustrated two-leg spin ladder with alternate isotropic Heisenberg and Ising rung exchange interactions, whereas, interactions along legs and diagonals are Ising-type. All the interactions in the ladder are anti-ferromagnetic in…

Strongly Correlated Electrons · Physics 2020-11-25 Sk Saniur Rahaman , Shaon Sahoo , Manoranjan Kumar

Orbit-based methods are widespread in strong-field laser-matter interaction. They provide a framework in which photoelectron momentum distributions can be interpreted as the quantum interference between different semi-classical pathways the…

Atomic Physics · Physics 2024-10-03 T. Rook , D. Habibović , C. Figueira de Morisson Faria

Singularity analysis is essential in robot kinematics, as singular configurations cause loss of control and kinematic indeterminacy. This paper models singularities in bar frameworks as saddle points on constrained manifolds. Given an…

Robotics · Computer Science 2025-10-31 Xuenan Li , Mihnea Leonte , Christian D. Santangelo , Miranda Holmes-Cerfon