Site-specific magnetization reversal studies of magnetite

Abstract

The mechanism of magnetization reversal in magnetite ͑Fe 3 O 4 ͒ single crystals was studied using sitespecific magnetic sensitive diffraction anomalous near-edge structure. By exploiting the angular dependence of the cross section, we are able to show that the mechanism of reversal involves a mixture of coherent rotation and domain formation. The results reveal additional details to that provided by XMCD measurements, which average over nonequivalent sites.

Fabrication of spin-polarized electron emitter with single ⟨110⟩-oriented magnetite whisker

“…For this microsampling, the voltage line to the manipulator should be disconnected; otherwise, many whiskers become attached to the approaching manipulator due to electrostatic attraction. 27 In the case of spin moments being oriented along the long ͗110͘ axis of the whisker due to magnetic anisotropy, the estimated polarization has become lower than the true value because our experimental system cannot detect spin components parallel to the long axis of a whisker due to the lack of a spin rotator. ͑e͒ Tungsten was deposited and the tip of the whisker was joined Fig.…”

Chirality in metals: An asymmetrical journey among advanced functional materials

“…In the rare-earth metal holmium, magnetic moments in the atomic plane give rise to a magnetic spiral, the helical arrangement results in a chirality driven by electronic structure. [9][10][11] Chiral structures are also known for intermetallic compounds. If we consider scandium, a metal known to form a huge number of binary and ternary compounds, out of the 170 known binary compounds only B 15 Sc crystallises in a chiral space group (P4 1 ); while among ternary scandium-based intermetallic compounds, 12 crystallise in chiral space groups: Sc 3 InS 6 (P2 1 2 1 2), AgScSe 2 (P2 1 2 1 2 1 ), Sc 5+x Cu 12 Examples of these structures are shown in Fig.…”

“…In the rare-earth metal holmium, magnetic moments in the atomic plane give rise to a magnetic spiral, the helical arrangement results in a chirality driven by electronic structure. 9–11…”

Mössbauer Magnetic Scan experiments

“…However, in cases in which the same element is located at non equivalent sites, for example Fe in magnetite, the dichroism signal is an average over these sites. Indeed, the problem on how the atomic magnetic-moments, located at octahedral and tetrahedral sites in this compound, individually respond to an applied magnetic field has been addressed by a more sophisticated synchrotron technique: site-specific diffraction anomalous near-edge structure [3]. This advantageous type of observation is not provided by most commonly used magnetometric techniques, which frequently give only information on the average magnetic moment component in one space direction.…”