English
Related papers

Related papers: Dislocation-induced spin tunneling in Mn-12 acetat…

200 papers

Inelastic tunneling through magnetically anisotropic molecules is studied theoretically in the presence of a strong magnetic field. Since the molecular orientation is not well controlled in tunneling experiments, we consider arbitrary…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Carsten Timm

A single-molecule magnet placed in a magnetic field perpendicular to its anisotropy axis can be truncated to an effective two-level system, with easily tunable energy splitting. The quantum coherence of the molecular spin is largely…

Mesoscale and Nanoscale Physics · Physics 2015-06-17 A. Morello , A. Millán , L. J. de Jongh

Crystals of the molecular magnet Mn12-acetate are known to contain a small fraction of low- symmetry (minor) species with a small anisotropy barrier against spin reversal. The lower barrier leads to faster magnetic relaxation and lower…

Other Condensed Matter · Physics 2009-11-13 S. McHugh , R. Jaafar , M. P. Sarachik , Y. Myasoedov , H. Shtrikman , E. Zeldov , R. Bagai , G. Christou

Spin-polarized transport through bistable magnetic adatoms or single-molecule magnets (SMMs), which exhibit both uniaxial and transverse magnetic anisotropy, is considered theoretically. The main focus is on the impact of transverse…

Mesoscale and Nanoscale Physics · Physics 2014-07-22 Maciej Misiorny , Józef Barnaś

Spin-phonon relaxation due to two-phonon processes of a spin cluster embedded in an elastic medium has been studied. For the case of uniaxial anisotropy, relaxation rates due to Raman processes and processes involving the emission of two…

Statistical Mechanics · Physics 2008-05-05 C. Calero , E. M. Chudnovsky , D. A. Garanin

Surface scattering is the key limiting factor to thermal transport in dielectric crystals as the length scales are reduced or when temperature is lowered. To explain this phenomenon, it is commonly assumed that the mean free paths of heat…

Materials Science · Physics 2017-08-17 Andrea Cepellotti , Nicola Marzari

When charge current passes through a normal metal that exhibits spin Hall effect, spin accumulates at the edge of the sample in the transverse direction. We predict that this spin accumulation, or spin voltage, enables quantum tunneling of…

Mesoscale and Nanoscale Physics · Physics 2016-09-21 Wei Chen , Manfred Sigrist , Dirk Manske

New Mn12 single-molecule magnets (SMM's) with the composition [Mn12O12(O2CR)16(H2O)4] were prepared and structurally characterized. Complexes of this type can exhibit two out-of-phase ac magnetic susceptibility signals, one in the 4-7 K…

We observe anisotropic Hanle lineshape with unequal in-plane and out-of-plane non-local signals for spin precession measurements carried out on lateral metallic spin valves with transparent interfaces. The conventional interpretation for…

Mesoscale and Nanoscale Physics · Physics 2017-02-09 K. S. Das , F. K. Dejene , B. J. van Wees , I. J. Vera-Marun

Spin relaxation torque ${\cal T}$ in uniform metallic ferromagnets with the spin-orbit interaction arising from random impurities is calculated microscopically. ${\cal T}$ is shown to be written by spatial derivatives of the electric field,…

Mesoscale and Nanoscale Physics · Physics 2015-05-18 Noriyuki Nakabayashi , Akihito Takeuchi , Kazuhiro Hosono , Katsuhisa Taguchi , Gen Tatara

Below 360 mK, Fe magnetic molecular clusters are in the pure quantum relaxation regime and we show that the predicted square-root time relaxation is obeyed, allowing us to develop a new method for watching the evolution of the distribution…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 W. Wernsdorfer , T. Ohm , C. Sangregorio , R. Sessoli , D. Mailly , C. Paulsen

Low-temperature measurements of the magnetocrystalline anisotropy energy $K$ in (Fe$_{1-x}$Co$_{x}$)$_{2}$B alloys are reported, and the origin of this anisotropy is elucidated using a first-principles electronic structure analysis. The…

It is demonstrated by SQUID magnetization measurements that (Ga,Mn)As films can exhibit rich characteristics of magnetic anisotropy depending not only to the epitaxial strain but being strongly influenced by the hole and Mn concentration,…

MnSi is an itinerant magnet which at low temperatures develops a helical spin density wave. Under pressure it undergoes a transition into an unusual partially ordered state whose nature is debated. Here we propose that the helical spin…

Strongly Correlated Electrons · Physics 2009-11-11 B. Binz , A. Vishwanath , V. Aji

We present a quantum transport theory for generic magnetic metals, in which magnetism occurs predominantly due to exchange interactions, such as ferromagnets, antiferromagnets, altermagnets and p-wave magnets. Our theory is valid both for…

Superconductivity · Physics 2025-06-11 Tim Kokkeler , Ilya Tokatly , F. Sebastian Bergeret

Based on micromagnetic theory we have derived analytical expressions for the magnetic small-angle neutron scattering (SANS) cross section of a two-phase particle-matrix-type ferromagnet. The approach---valid close to magnetic…

Mesoscale and Nanoscale Physics · Physics 2020-07-27 Dirk Honecker , Andreas Michels

We study the effect of uniaxial pressure on the magnetic hysteresis loops of the single-molecule magnet Mn_{12}-Ac. We find that the application of pressure along the easy axis increases the fields at which quantum tunneling of…

Mesoscale and Nanoscale Physics · Physics 2013-06-12 J. H. Atkinson , K. Park , C. C. Beedle , D. N. Hendrickson , Y. Myasoedov , E. Zeldov , Jonathan R. Friedman

We solve appropriate drift-diffusion and Landau-Lifshitz-Gilbert equations to demonstrate that unpolarized current flow from a non-magnet into a ferromagnet can produce a precession-type instability of the magnetization. The fundamental…

Materials Science · Physics 2009-11-10 M. D. Stiles , Jiang Xiao , A. Zangwill

We present a theory of magnetic anisotropy in ${\rm III}_{1-x}{\rm Mn}_{x}{\rm V}$ diluted magnetic semiconductors with carrier-induced ferromagnetism. The theory is based on four and six band envelope functions models for the valence band…

Materials Science · Physics 2009-10-31 M. Abolfath , T. Jungwirth , J. Brum , A. H. MacDonald

We describe a theory of Mn local-moment magnetization relaxation due to p-d kinetic-exchange coupling with the itinerant-spin subsystem in the ferromagnetic semiconductor (Ga,Mn)As alloy. The theoretical Gilbert damping coefficient implied…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Jairo Sinova , T. Jungwirth , X. Liu , Y. Sasaki , J. K. Furdyna , W. A. Atkinson , A. H. MacDonald