000136210 001__ 136210
000136210 005__ 20240719195438.0
000136210 0247_ $$2doi$$a10.1088/2515-7639/ad558b
000136210 0248_ $$2sideral$$a139138
000136210 037__ $$aART-2024-139138
000136210 041__ $$aeng
000136210 100__ $$aDelgado, Fernando
000136210 245__ $$aSpin wave excitations in low dimensional systems with large magnetic anisotropy
000136210 260__ $$c2024
000136210 5060_ $$aAccess copy available to the general public$$fUnrestricted
000136210 5203_ $$aThe low-energy excitation spectrum of a two-dimensional ferromagnetic material is dominated by single-magnon excitations that show a gapless parabolic dispersion relation with the spin wave vector. This occurs as long as magnetic anisotropy and anisotropic exchange are negligible compared to isotropic exchange. However, to maintain magnetic order at finite temperatures in extended systems, it is necessary to have sizable anisotropy to open a gap in the spin wave excitation spectrum. We consider four real two-dimensional systems for which ferromagnetic order at finite temperature has been observed or predicted. Density functional theory calculations of the total energy differences for different spin configurations permit us to extract the relevant parameters and connect them with a spin Hamiltonian. The corresponding values of the Curie temperature are estimated using a simple model and found to be mostly determined by the value of the isotropic exchange. The exchange and anisotropy parameters are used in a toy model of finite-size periodic chains to study the low-energy excitation spectrum, including single-magnon and two-magnon excitations. At low energies, we find that single-magnon excitations appear in the spectrum together with two-magnon excitations. These excitations present a gap that grows particularly for large values of the magnetic anisotropy or anisotropic exchange, relative to the isotropic exchange.
000136210 536__ $$9info:eu-repo/grantAgreement/ES/MICINN-AEI/PRTR-C17.I1$$9info:eu-repo/grantAgreement/ES/MICINN/PID2019-103910GB-I00$$9info:eu-repo/grantAgreement/ES/MICINN/PID2022-137685NB-I00$$9info:eu-repo/grantAgreement/ES/MICINN/PID2022-138210NB-I00$$9info:eu-repo/grantAgreement/ES/MICINN/PID2022-138269NB-I00
000136210 540__ $$9info:eu-repo/semantics/openAccess$$aby$$uhttp://creativecommons.org/licenses/by/3.0/es/
000136210 655_4 $$ainfo:eu-repo/semantics/article$$vinfo:eu-repo/semantics/publishedVersion
000136210 700__ $$aOtrokov, Mikhail M
000136210 700__ $$aArnau, Andrés
000136210 773__ $$g7, 3 (2024), 035005 [10 pp.]$$tJPhys Materials$$x2515-7639
000136210 8564_ $$s628603$$uhttps://zaguan.unizar.es/record/136210/files/texto_completo.pdf$$yVersión publicada
000136210 8564_ $$s2692457$$uhttps://zaguan.unizar.es/record/136210/files/texto_completo.jpg?subformat=icon$$xicon$$yVersión publicada
000136210 909CO $$ooai:zaguan.unizar.es:136210$$particulos$$pdriver
000136210 951__ $$a2024-07-19-18:29:23
000136210 980__ $$aARTICLE