In a simple system pay attention to that word, a ferromagnetic coupling implies that j 0. Ferromagnetic and antiferromagnetic coupling of spin molecular. Another antiferromagnetic example is k 2 ircl 6 dimeric salt where exchange couplings occur through superexchange mechanism detectable by epr. Strong antiferromagnetic coupling in doubly n, o oximatobridged dinuclear copperii complexes. Mechanism and control of antiferromagnetic coupling in fefe3o4. Antiferromagnetic coupling and enhanced magnetization in allferromagnetic superlattices.
The robust antiferromagnetic coupling is stabilized by a superexchange interaction, driven by the outofplane molecular orbitals responsible. Pdf study of antiferromagnetic coupling by ferromagnetic. Fe iii cn 6 chain complex with highly anisotropic fe. The emergence of this order is accompanied by magnetoelastic coupling, which drives anisotropic negative t in celebration of tony cheethams 70th birthday. In this way, it differs from direct exchange in which there is coupling between nearest neighbor cations not involving an intermediary anion. We consider theoretically the impact of rashba spinorbit coupling on spin torque oscillators stos in synthetic ferromagnets and antiferromagnets that have either a. Currentinduced spinorbit torques mediate the transfer of angular momentum from the lattice to the spin system, leading to. Chandran karunakaran, murugesan balamurugan, in spin resonance spectroscopy, 2018. Files available from the acs website may be downloaded for personal use only. This is because when the transition metal is oxidized, the antiferromagnetic property is more common by the superexchange effect and the spinorbit coupling soc 22, 23 such as caxo x mn, cr 24, 25 and xo x 3d ferromagnetic elements. Antiferromagneticferromagnetic coupling physics forums. Antiferromagnetic coupling by spin polarized tunneling. Hill b a science division, truman state university, kirksville, mo 63501 b department of physics, university of florida, gainesville, fl 32611 abstract electron spin resonance was used to study the spindimer compound. Slow magnetic relaxation, antiferromagnetic ordering, and.
On the other hand, j kl is the exchange coupling energy between the f k and f l layers, where the positive negative j kl corresponds to the energy of ferromagnetic antiferromagnetic coupling. It was shown that parallel coupling is stable for junctions without extra fe atoms whereas ap coupling becomes stable when the number of extra fe atoms. From antiferromagnetic to ferromagnetic coupling for v. Therefore, we tried to realize antiferromagnetic characteristics by oxidation of fgt. Crystal09 users manual university of torino, torino. Back1 1institute for experimental and applied physics, university of regensburg, universitaetstrasse 31. It was grown magnetically to dilute single crystals of about 5% k 2 ircl 6 in a diamagnetic k 2 ptcl 6 host lattice. Exchange coupling of co and fe on antiferromagnetic nio. Antiferromagnetic coupling between ferromagnetic layers has been observed for the first time in allsemiconductor superlattice structure euspbs001, by. This is a typical transition metal system in which antiferromagnetic coupling is of interest. Superexchange, or kramersanderson superexchange, is the strong usually antiferromagnetic coupling between two nexttonearest neighbour cations through a nonmagnetic anion. Spinorbit coupling in inversionasymmetric magnetic crystals and structures has emerged as a powerful tool to generate complex magnetic textures, interconvert charge and spin under applied current, and control magnetization dynamics. The exact determination of what j is for any given system is usually impossible to find exactly. Pdf antiferromagnetic coupling by spin polarized tunneling.
Coupling the valley degree of freedom to antiferromagnetic order xiao li a, ting cao a,b, qian niu a,c, junren shi a, and ji feng a,1 ainternational center for quantum materials, peking university, beijing 100871, china. Antiferromagnetic coupling in copperiiporphyrin dimers. Pdf from antiferromagnetic to ferromagnetic coupling for v. Thompson,3 lapo bogani,1 fernando luis,4 stephen j. Giant magnetoresistance in perpendicularly magnetized. Conventional electronics are based invariably on the intrinsic degrees of freedom of an electron, namely, its charge and spin. In terms of the magnetic field, h jkl j kl m k d k, the coupling in psaf is 17. We evidence that the relative strength of the interlayer exchange coupling j to the uniaxial anisotropy k controls a transition from an atype antiferromagnetic order to a ferromagneticlike metamagnetic state. In this paper, the broken symmetry approach within density functional theory dftbs7,8 is used to investigate the anti ferromagnetic properties of the ag i complex and to study the magnetostructural correlations for the ag i. Interlayer couplings mediated by antiferromagnetic magnons. In the netural molecule, in which the mn atoms are nominally mnii, there are 5 d electrons. Antiferromagnetic coupling in ferromagneticferrimagnetic.
Strong coupling of microwave photons to antiferromagnetic fluctuations in an organic magnet matthias mergenthaler,1,2, junjie liu,1 jennifer j. We report an advanced organic spininterface architecture with magnetic remanence at room temperature, constituted by metal. Study of antiferromagnetic coupling by ferromagnetic resonance fmr article pdf available in journal of magnetism and magnetic materials 17623. Different antiferromagnetic coupling between 5,5 and 10,10linked ironiii corrole dimers. Laird1, 1department of materials, university of oxford, oxford ox1. Antiferromagnetic coupling in perpendicularly magnetized cubic and.
The robust antiferromagnetic coupling is stabilized by a superexchange interaction, driven by the outofplane molecular orbitals responsible of the magnetic ground state and electronically decoupled from the underlying metal via the graphene layer, as confirmed by ab initio theoretical predictions. Antiferromagnetic coupling is an effect that is often important for molecules with high spin multiplicity like this bridged manganese complex. Antiferromagnetic an overview sciencedirect topics. Strong coupling of microwave photons to antiferromagnetic. Unlimited viewing of the articlechapter pdf and any associated supplements and figures. In small external fields such double layers order antiparallel with their magnetization perpendicular to the external field in analogy to the spin. A bilayer stonerwohlfarth model allows us to describe this evolution, as well as the typical angular. For semihydrogenated sic, it is ferromagnetic when all hydrogen atoms bond with silicon atoms, while an antiferromagnetic coupling is predicted when all. Co adipate, coc6h8o4, has been found to order near 10 k into a magnetic structure featuring sheets of tetrahedral co cations coupled antiferromagnetically in two dimensions through carboxylate groups. The results obtained in the case of a submonolayer coverage are in agreement with recent xray magnetic circular dichroism by huttel et al. Aip advances 1, 042155 2011 anomalous antiferromagnetic coupling in fesife structures with co dusting r. Band gap characters and ferromagneticantiferromagnetic. By controlling the thickness of an antiferromagnetic and ferromagnetic layer, interfacial ionic polarization, as well as the transformation between ferromagnetic and magnetic. Slow magnetic relaxation, antiferromagnetic ordering, and metamagnetism in mn ii h 2 dapsc.
Collinear antiferromagnets afs support two degenerate magnon excitations carrying opposite spin polarizations, by which magnons can function as electrons in various spinrelated phenomena. Overcoming the limits of the interfacial dzyaloshinskii. For submonolayer coverage the coupling between v and co is clearly of antiferromagnetic type whereas it changes to ferromagnetic coupling in the case of a full v monolayer on co001. Ubiquitous longrange antiferromagnetic coupling across the. Coupling the valley degree of freedom to antiferromagnetic.
Different antiferromagnetic coupling between 5,5 and 10. In an insulating ferromagnetfaff trilayer, we explore the magnonmediated interlayer coupling by calculating the magnon thermal energy in the. Pdf we have worked out the ferromagnetic resonance fmr mode characteristics of an antiferromagnetically coupled twolayer film system. Users are not otherwise permitted to reproduce, republish.
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