Magnetic structure

About: Magnetic structure is a research topic. Over the lifetime, 10787 publications have been published within this topic receiving 207143 citations.

Magnetic Structure of an Amorphous Rare-Earth Transition-Metal Alloy

Abstract: /sup 161/Dy Mossbauer spectra show that the dysprosium moments in amorphous DyCo/sub 3.4/ are strongly coupled to the local crystal field axes. The magnetic structure is one in which the cobalt ''sublattice'' is strongly ferromagnetic, and the dysprosium moments are almost randomly distributed in directions between antiparallel and perpendicular to the cobalt. (AIP)

Spin-rotation phenomena and magnetic phase diagrams of hexagonal RMnO3

Abstract: Magnetic phase diagrams of the hexagonal RMnO3 (with R=Sc, Y, Ho, In, Er, Tm, Yb, Lu) compounds in the magnetic-field/temperature plane are established by linear and nonlinear magneto-optical techniques. Eight different magnetic phases of the Mn3+ sublattice and at least three different phases of the R3+ sublattices are distinguished. Phase coexistence and photoinduced modification of the magnetic structure are observed. Magnetic reorientations of the Mn3+ lattice can occur via in-phase or antiphase rotation of the triangularly frustrated spins in the adjacent crystallographic planes.

Electronic structure and magnetic ordering of the semiconducting chromium trihalides CrCl3, CrBr3, and CrI3

Abstract: We present results from an electronic structure investigation of the chromium halides CrCl(3), CrBr(3), and CrI(3), as obtained by the linearized augmented plane wave method of density functional theory. Our interest focuses on the chloride. While all three halides display strong ferromagnetic coupling within the halide-Cr-halide triple layers, our emphasis is on differences in the interlayer magnetic coupling. In agreement with experimental results, our calculations indicate ferromagnetic ordering for CrBr(3) as well as CrI(3). The antiferromagnetic state of CrCl(3) can be reproduced by introducing an on-site electron-electron repulsion. However, we observe that the ground state depends critically on the specific approach used. Our results show that a low temperature structural phase transition from monoclinic to trigonal is energetically favourable for CrCl(3).

Laser-Induced Intersite Spin Transfer.

Abstract: Laser pulses induce spin-selective charge flow that we show to generate dramatic changes in the magnetic structure of materials, including a switching of magnetic order from antiferromagnetic (AFM) to transient ferromagnetic (FM) in multisub-lattice systems. The microscopic mechanism underpinning this ultrafast switching of magnetic order is dominated by spin-selective charge transfer from one magnetic sublattice to another. Because this spin modulation is purely optical in nature (i.e., not mediated indirectly via the spin–orbit interaction) this is one of the fastest means of manipulating spin by light. We further demonstrate this mechanism to be universally applicable to AFM, FM, and ferri-magnets in both multilayer and bulk geometry and provide three rules that encapsulate early-time magnetization dynamics of multisub-lattice systems.

Emergent magnetic monopole dynamics in macroscopically degenerate artificial spin ice.

Abstract: Magnetic monopoles, proposed as elementary particles that act as isolated magnetic south and north poles, have long attracted research interest as magnetic analogs to electric charge. In solid-state physics, a classical analog to these elusive particles has emerged as topological excitations within pyrochlore spin ice systems. We present the first real-time imaging of emergent magnetic monopole motion in a macroscopically degenerate artificial spin ice system consisting of thermally activated Ising-type nanomagnets lithographically arranged onto a pre-etched silicon substrate. A real-space characterization of emergent magnetic monopoles within the framework of Debye-Huckel theory is performed, providing visual evidence that these topological defects act like a plasma of Coulomb-type magnetic charges. In contrast to vertex defects in a purely two-dimensional artificial square ice, magnetic monopoles are free to evolve within a divergence-free vacuum, a magnetic Coulomb phase, for which features in the form of pinch-point singularities in magnetic structure factors are observed.