First-principles prediction of sub-10 nm skyrmions in Pd/Fe bilayers on Rh(111)

• Published in: arXiv.org
• Main Authors: Haldar, Soumyajyoti, Stephan von Malottki, Meyer, Sebastian, Bessarab, Pavel F, Heinze, Stefan
• Format: Paper Journal Article
• Language: English
• Published: Ithaca Cornell University Library, arXiv.org 16.06.2018
• Subjects: Anisotropy; Bilayers; Computer simulation; Density functional theory; First principles; Hypothetical particles; Magnetic fields; Particle theory; Physics - Materials Science; Rhodium; Spin dynamics; Spin-orbit interactions; Transition metals
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.1806.06234

We show that stable skyrmions with diameters of a few nanometers can emerge in atomic Pd/Fe bilayers on the Rh(111) surface. Based on density functional theory we calculate the exchange and the Dzyaloshinskii-Moriya interaction as well as the magnetocrystalline anisotropy energy. The later two terms are driven by spin-orbit coupling and significantly reduced compared to Pd/Fe bilayers on Ir(111) as expected since Rh and Ir are isoelectronic \(4d\) and \(5d\) transition-metals. However, there is still a spin spiral ground state at zero magnetic field. Atomistic spin dynamics simulations show that a skyrmion phase occurs at small magnetic fields of \(\sim\) 1 T. Skyrmion diameters amount to 2 to 8 nm and skyrmion lifetimes are up to 1 hour at temperatures of 25 to 45 K.