Magnetic structure of bulk GdMnO₃: Influence of strain

Internal structural distortions are of great interest in the determination of electronic and magnetic properties of the strong correlated rare earth manganites. When combined with external structural modifications like uniaxial or biaxial strains, structural distortions can lead to the emergence of new magnetic ground states. This realization is seemingly more probable with the low-band-width manganite GdMnO3 on the grounds that it is located in the magnetoelectric phase diagram of orthorhombic rare earth manganites between the A-type antiferromagnetic (AFM) order and the cycloidal spin orders. Herein, a thorough analysis of the magnetic structure of GdMnO3 based on the density functional theory connected with a classical Heisenberg model together with Monte Carlo calculations is presented. It is found whether a compressive uniaxial strain along the c direction or biaxial strain on the ab plane favors a ferromagnetic (FM) ground state over the AFM one. On the contrary, a tensile strain also on the ab plane is likely to stabilize the E-type AFM order

Electronic and magnetic properties of BaFeO₃ on the Pt(111) surface in a quasicrystalline approximant structure

Perovskite‐like ABO3 oxides A = (Ca, Sr, Ba) and B = (Ti, Mn, Fe, Co, Ni) show a large variety of structures and physical properties. Among them is BaTiO3 (BTO), one of the most investigated and used perovskites. In a BTO film on Pt(111), the first oxide quasicrystal was discovered. Herein, by means of first‐principle methods, the cubic and hexagonal phases of bulk BaFeO3 (BFO) are investigated. Both phases show ferromagnetic order. Monolayers and double layers of BFO are studied on a Pt(111) surface. The double‐layer configuration of the cubic and hexagonal phases is structurally inequivalent but both double‐layer films show antiferromagnetic order. In analogy to the BTO quasicrystal approximant structure on Pt(111), a corresponding BFO structure is investigated. The Fe atoms are surrounded by three oxygen atoms and the resulting FeO3 units are separated by barium atoms with the total stoichiometry Ba5Fe4O12

Advances in methods to obtain and characterise room temperature magnetic ZnO

We report the existence of magnetic order at room temperature in Li-doped ZnO microwires after low energy H+ implantation. The microwires with diameters between 0.3 and 10 μm were prepared by a carbothermal process. We combine spectroscopy techniques to elucidate the influence of the electronic structure and local environment of Zn, O, and Li and their vacancies on the magnetic response. Ferromagnetism at room temperature is obtained only after implanting H+ in Li-doped ZnO. The overall results indicate that low-energy proton implantation is an effective method to produce the necessary amount of stable Zn vacancies near the Li ions to trigger the magnetic order.Fil: Lorite, I.. Fakultät für Physik und Geowissenschaften; AlemaniaFil: Straube, Benjamin. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Departamento de Física. Laboratorio de Física del Solido; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ohldag, H.. University Of Stanford; Estados UnidosFil: Kumar, P.. Fakultät für Physik und Geowissenschaften; AlemaniaFil: Villafuerte, Manuel Jose. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Departamento de Física. Laboratorio de Física del Solido; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Esquinazi, P.. Fakultät für Physik und Geowissenschaften; AlemaniaFil: Rodriguez Torres, Claudia Elena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto de Física La Plata; ArgentinaFil: Perez de Huelani, S.. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Departamento de Física. Laboratorio de Física del Solido; ArgentinaFil: Antonov, V. N.. Institute for Metal Physics; Ucrania. Max Planck Institut für Mikrostrukturphysik; AlemaniaFil: Bekenov, L. V.. Institute for Metal Physics; Ucrania. Max Planck Institut für Mikrostrukturphysik; AlemaniaFil: Ernst, A.. Max Planck Institut für Mikrostrukturphysik; Alemania. Universitat Leipzig; AlemaniaFil: Hoffmann, M.. Max Planck Institut für Mikrostrukturphysik; Alemania. Martin Luther University Halle-Wittenberg; AlemaniaFil: Nayak, S. K.. Martin Luther University Halle-Wittenberg; AlemaniaFil: Adeagbo, W. A.. Martin Luther University Halle-Wittenberg; AlemaniaFil: Fischer, G.. Max Planck Institut für Mikrostrukturphysik; AlemaniaFil: Hergert. W.. Martin Luther University Halle-Wittenberg; Alemani