Magnetoelectric coupling at metal surfaces

Reduced-dimensionality-induced helimagnetism in iron nanoislands

“…1d), indicative of a biatomic layer. The STS spectra identify the island as the structural phase Fe-b 20,21 (Supplementary Fig. 1; Supplementary Note 1).…”

“…It has been proposed that an extended BL Fe film on Cu(111) favours fcc stacking ('Fe-a' phase) with a prediction of AFM spin ordering 20 . In contrast, BL Fe nanoislands on Cu(111) with a reduced lateral size (oB10 nm) predominantly show an intriguing lattice structure, which favours a bridge-site-stacking of topmost Fe atoms 20,21 ('Fe-b' phase).…”

“…It has been proposed that an extended BL Fe film on Cu(111) favours fcc stacking ('Fe-a' phase) with a prediction of AFM spin ordering 20 . In contrast, BL Fe nanoislands on Cu(111) with a reduced lateral size (oB10 nm) predominantly show an intriguing lattice structure, which favours a bridge-site-stacking of topmost Fe atoms 20,21 ('Fe-b' phase). Fe is a prototypical example for studying the impact of structural relaxations on the exchange interaction, because of the pronounced interatomic distance dependence of the magnetic ordering 17,18 .…”

Ferroelectric Field Effect Control of Magnetism in Multiferroic Heterostructures

“…The nature of the magnetoelectric effect due to charge screening can be distinguished between (i) enhanced spin imbalance at the Fermi level due to screening and the corresponding modification in the magnetic moment of the system as a function of the electric field Zhang (1999); (ii) changes in magnetic moment due to changes in electronic bonding at the polarized dielectric interface Duan et al (2006); (iii) changes in the magnetic order with the charge density Gerhard et al (2010); Kudasov & Korshunov (2007); Ovchinnikov & Wang (2008); Sun et al (2010); Vaz et al (2010b), whereby the magnetic state of the system is modified due to changes in the charge carrier density, either between magnetic and non-magnetic states, or between states with different magnetic spin configurations; and (iv) changes in the magnetic anisotropy that lead to different global magnetic states for different applied electric fields Maruyama et al (2009);Niranjan et al (2010).…”

“…More recently, Maruyama et al (2009) Endo et al (2010b). Another demonstration of electric field modulation of magnetism relies on the magnetic and structural instabilities of elemental Fe, where the application of an electric field is found to induce changes in the crystal structure of Fe/Cu(111) islands, from the ferromagnetic bcc to the antiferromagnetic fcc structure Gerhard et al (2010); first principles calculations show that the effect originates from changes in the Fe interatomic distances with the applied electric field as a result of electronic charge screening that tilts the energy of the system to favor a ferromagnetic or antiferromagnetic state Gerhard et al (2010). The theoretical study of the magnetoelectric coupling in metal-based multiferroic heterostructures has been the subject of intensive investigation.…”