Programme

P.42 -- Posters, VCTP-51

Date: Tuesday, 4 August 2026

Time: 09:30 - 10:30

Tuning Noncollinear RKKY Interactions in Altermagnets via Adiabatic Electron–Phonon Coupling

Bui D. Hoi (1)

Faculty of Physics, University of Education, Hue University

Altermagnets, characterized by vanishing net magnetization and momentum-dependent spin splitting, provide a promising platform for spintronic applications owing to their unconventional spin textures and tunable magnetic properties. In this work, we investigate the Ruderman–Kittel–Kasuya–Yosida (RKKY) interaction in two-dimensional Rashba d-wave altermagnets in the presence of adiabatic electron–phonon coupling and arbitrary Rashba spin–orbit coupling (RSOC). Employing a continuum model that incorporates altermagnetic order, Rashba spin–orbit interaction, and spin-dependent static-Holstein lattice distortions, we calculate the noncollinear RKKY exchange tensor using second-order perturbation theory combined with numerical momentum-space integration. Our results demonstrate that adiabatic lattice distortions provide an effective mechanism for controlling the strength, anisotropy, phase, and chirality of RKKY interactions. Increasing electron–phonon coupling generally suppresses long-range exchange coherence while inducing pronounced component-dependent phase shifts and sign reversals, particularly in the Dzyaloshinskii–Moriya and compass-like exchange terms. These effects enable transitions between ferromagnetic and antiferromagnetic alignments as well as reversals of clockwise and counterclockwise chiral magnetic configurations. Furthermore, the interplay among altermagnetic order, RSOC, electron–phonon coupling, and carrier doping gives rise to increasingly complex oscillatory behaviors of the exchange interaction. The present study identifies slow phonons as a versatile low-energy tuning parameter for engineering noncollinear magnetic interactions in altermagnets, offering a practical route toward controlling magnetic textures and chiral spin states in altermagnet-based spintronic heterostructures.

Presenter: Bui D. Hoi