Prediction of 2D ferromagnetism and monovalent europium ions in EuBr/graphene heterojunctions
| Autor: | Gianfranco Pacchioni, Haoyi Tan, Guangcun Shan |
|---|---|
| Přispěvatelé: | Tan, H, Shan, G, Pacchioni, G |
| Rok vydání: | 2021 |
| Předmět: |
Condensed Matter - Materials Science
Materials science Spintronics Condensed Matter - Mesoscale and Nanoscale Physics Graphene General Physics and Astronomy chemistry.chemical_element Materials Science (cond-mat.mtrl-sci) FOS: Physical sciences magnetism thin films Electron localization function law.invention Condensed Matter::Materials Science chemistry Ferromagnetism Chemical physics law Monolayer Mesoscale and Nanoscale Physics (cond-mat.mes-hall) Curie temperature Density functional theory Condensed Matter::Strongly Correlated Electrons Physical and Theoretical Chemistry Europium |
| Zdroj: | Physical chemistry chemical physics : PCCP. 23(45) |
| ISSN: | 1463-9084 |
| Popis: | Europium, one of the rare earth elements, exhibits +2 and +3 valence states and has been widely used for magnetic modification of materials. Based on density functional theory calculations, we predict the 2D EuBr/graphene heterojunctions to exhibit metallicity, huge intrinsic-ferromagnetism nearly 7.0 {\mu}B per Eu and the special monovalent Eu ions. Electron localization function (ELF), difference charge densities and Bader charge analyses demonstrate that there are cation-{\pi} interactions between the EuBr films and graphene, which explains the stability of these unusual heterojunctions. Graphene works as substrate to enable the stability of EuBr monolayer crystals where EuBr plays an important role to yield ferromagnetism and enhance metallicity in the heterojunctions. Monte Carlo simulations are used to estimate a Curie temperature of about 7 K, which, together with magnetic configurations, can be further modulated by external strains and charge-carrier doping. In general, our theoretical work predicts the properties of the novel 2D ferromagnetic EuBr/graphene heterojunctions, suggests the possibility of combining the 2D intrinsic-ferromagnetic metal halide crystals and graphene, and opens up a new perspective in next-generation electronic, spintronic devices and high-performance sensors. Comment: 22 pages, 6 figures |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|