English
Related papers

Related papers: Fronts of spin tunneling in molecular magnets

200 papers

In this work, we study the spin dynamics of Mn12-acetate molecules in the regime of thermally assisted tunneling. In particular, we describe the system in the presence of a strong transverse magnetic field. Similar to recent experiments,…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 Teemu Pohjola , Herbert Schoeller

Spin-polarized current through an Al nanoparticle in tunnel contact with two ferromagnets is measured as a function of the direction of the applied magnetic field. The nanoparticle filters the spin of injected electrons along a direction…

Mesoscale and Nanoscale Physics · Physics 2008-09-15 F. T. Birk , C. E. Malec , D. Davidovic

We present a simple model of composite particle tunnelling through a rectangular potential barrier in presence of magnetic field. The exact numerical solution of the problem is provided and the applicability to real physical situations is…

Quantum Physics · Physics 2024-10-22 Bernard Faulend , Jan Dragašević

In magnetic fields applied parallel to the anisotropy axis, the relaxation of the magnetization of Mn$_{12}$ measured for different sweep rates is shown to collapse onto a single scaled curve. The form of the scaling implies that the…

The diffusion of a system of ferromagnetic dipoles confined in a quasi-one-dimensional parabolic trap is studied using Brownian dynamics simulations. We show that the dynamics of the system is tunable by an in-plane external homogeneous…

Soft Condensed Matter · Physics 2013-01-15 D. Lucena , W. P. Ferreira , F. F. Munarin , G. A. Farias , F. M. Peeters

We report measurements of magnetic switching and steady-state magnetic precession driven by spin-polarized currents in nanoscale magnetic tunnel junctions with low-resistance, < 5 Ohm-micron-squared, barriers. The current densities required…

We consider spin-dependent tunneling through a gallium arsenide barrier, a material which has no inversion symmetry. We are dealing with free electrons, with one effective mass and a spin-splitting in the barrier material. When we take into…

Mesoscale and Nanoscale Physics · Physics 2009-09-29 T. L. Hoai Nguyen , Henri-Jean Drouhin , Jean-Eric Wegrowe , Guy Fishman

The spin-dependent transport of the electrons tunneling through a resonant tunneling structure with ferromagnetic multi-terminal under dc and ac fields is explored by means of the nonequilibrium Green function technique. A general…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Zhen-Gang Zhu , Gang Su , Qing-Rong Zheng , Biao Jin

Understanding the magnetization dynamics induced by spin transfer torques in perpendicularly magnetized magnetic tunnel junction nanopillars and its dependence on material parameters is critical to optimizing device performance. Here we…

Mesoscale and Nanoscale Physics · Physics 2021-04-14 Jamileh Beik Mohammadi , Andrew D. Kent

A system exhibiting multiple simultaneously broken symmetries offers the opportunity to influence physical phenomena such as tunneling currents by means of external control parameters. Time-reversal symmetry and inversion symmetry are both…

Strongly Correlated Electrons · Physics 2007-05-23 J. Linder , M. S. Gronsleth , A. Sudbo

In magnetic fields applied parallel to the anisotropy axis, the magnetization of Mn$_{12}$ has been measured in response to a field that is swept back and forth across the resonances corresponding to steps $N=4,5,...9$. The fraction of…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 K. M. Mertes , Yoko Suzuki , M. P. Sarachik , Y. Myasoedov , H. Shtrikman , E. Zeldov , E. M. Rumberger , D. N. Hendrickson , G. Christou

We theoretically study the spin-polarized transport through a single-molecule magnet, which is weakly coupled to ferromagnetic leads, by means of the rate-equation approach. We consider both the ferromagnetic and antiferromagnetic…

Mesoscale and Nanoscale Physics · Physics 2012-03-22 Haiqing Xie , Qiang Wang , Bo Chang , Hujun Jiao , J. -Q. Liang

We report the spontaneous formation of bipolar magnetic structures in direct numerical simulations of stratified forced turbulence with an outer coronal envelope. The turbulence is forced with transverse random waves only in the lower…

Solar and Stellar Astrophysics · Physics 2013-10-30 Jörn Warnecke , Illa R. Losada , Axel Brandenburg , Nathan Kleeorin , Igor Rogachevskii

The effect of spin-disorder scattering on perpendicular transport in a magnetic monolayer is considered within the single-site Coherent Potential Approximation (CPA). The exchange interaction between a conduction electron and localized…

Disordered Systems and Neural Networks · Physics 2009-11-07 Alireza Saffarzadeh

Electronic transport through a single-molecule magnet Mn$_{12}$ in a two-terminal set up is calculated using the non-equilibrium Green's function method in conjunction with density-functional theory. A single-molecule magnet Mn$_{12}$ is…

Materials Science · Physics 2010-01-28 Salvador Barraza-Lopez , Kyungwha Park , Víctor García-Suárez , Jaime Ferrer

We present a comprehensive theory of the magnetization relaxation in a Mn12-acetate crystal in the high-temperature regime (T>1 K), which is based on phonon-assisted spin tunneling induced by quartic magnetic anisotropy and weak transverse…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 Michael N. Leuenberger , Daniel Loss

Spin-polarized tunneling in FMS/M/FMS double tunnel junctions where FMSs are ferromagnetic semiconductor layers and M is a metal spacer is studied theoretically within the single-site coherent potential approximation (CPA). The exchange…

Disordered Systems and Neural Networks · Physics 2009-11-07 Alireza Saffarzadeh

The discovery that a spin polarized current can exert a large torque on a ferromagnet through a transfusion of spin angular momentum, offers a new way to control a magnetization by simple current injection, without the help of an applied…

The conductance profiles of magnetic transition metal atoms, such as Fe, Co and Mn, deposited on surfaces and probed by a scanning tunneling microscope (STM), provide detailed information on the magnetic excitations of such nano-magnets. In…

Mesoscale and Nanoscale Physics · Physics 2013-05-30 Aaron Hurley , Nadjib Baadji , Stefano Sanvito

A new mechanism is proposed for the magnetization reversal of molecular nanomagnets such as \Fe8. In this process the spin tunnels from the lowest state near one easy direction to the first excited state near the opposite easy direction,…

Mesoscale and Nanoscale Physics · Physics 2015-05-30 Anupam Garg