Equilibrium Skyrmion-Antiskyrmion Lattice in Anisotropic Frustrated Chiral Magnets
ORAL
Abstract
We report the discovery of a thermodynamically stable skyrmion-antiskyrmion lattice (S-AL) in two-dimensional chiral magnets, a paradoxical phenomenon where skyrmions (Q = -1) and antiskyrmions (Q = 1) form a regular long-range ordered lattice despite their inherent propensity for mutual annihilation, akin to particle-antiparticle interactions. This net-zero global topological charge state, resulting from balanced populations of oppositely charged solitons, is demonstrated as a magnetic field-induced topological ground state in frustrated chiral magnets with competing anisotropic interactions—specifically Dzyaloshinskii-Moriya and frustrated exchange interactions where reduced symmetry (C1v ) plays a critical role.
We develop a micromagnetic model that describes the emergence of S-AL as a thermodynamically stable ground state. Using density functional theory and atomistic spin-lattice simulations, we identify three interfacial magnetic films— 2Fe/InSb(110), 2Fe/GaAs(110), and 2Fe/CdTe(110)—as ideal candidates. In these C1v symmetric heterostructures, exchange frustration and symmetry-enforced anisotropic interactions stabilize the net-zero lattice against annihilation. We reveal a magnetic field-driven ground state phase sequence: cycloidal spin-spiral → S-AL → conical spin-spiral → ferromagnet.
This finding establishes anisotropic frustrated chiral magnets as a material class enabling stable net-zero topological soliton lattices within a single magnetic layer, resolving the paradox of coexisting oppositely charged entities.
We develop a micromagnetic model that describes the emergence of S-AL as a thermodynamically stable ground state. Using density functional theory and atomistic spin-lattice simulations, we identify three interfacial magnetic films— 2Fe/InSb(110), 2Fe/GaAs(110), and 2Fe/CdTe(110)—as ideal candidates. In these C1v symmetric heterostructures, exchange frustration and symmetry-enforced anisotropic interactions stabilize the net-zero lattice against annihilation. We reveal a magnetic field-driven ground state phase sequence: cycloidal spin-spiral → S-AL → conical spin-spiral → ferromagnet.
This finding establishes anisotropic frustrated chiral magnets as a material class enabling stable net-zero topological soliton lattices within a single magnetic layer, resolving the paradox of coexisting oppositely charged entities.
–
Publication: [1] S. Banik and A. K. Nandy, Skyrmion–antiskyrmion lattice: A net-zero topological phase in low-symmetry frustrated chiral magnets, Phys. Rev. B 112, L140404 (2025).
https://doi.org/10.1103/pcj5-gtrg
[2] S. Banik, N. S. Kiselev, and A. K. Nandy, Paradoxical Topological Soliton Lattice in Anisotropic Frustrated Chiral Magnets, arXiv:2510.22580 [cond-mat.mtrl-sci] (2025).
URL: https://arxiv.org/abs/2510.22580
Presenters
-
Sayan Banik
- National Institute of Science Education and Research