English
Related papers

Related papers: Tunable Magnetic Relaxation In Magnetic Nanopartic…

200 papers

We study the relaxation characteristics in the two-dimensional ($l^{}_x \times l^{}_y$) array of magnetic nanoparticles (MNPs) as a function of aspect ratio $A^{}_r=l^{}_y/l^{}_x$, dipolar interaction strength $h^{}_d$ and anisotropy axis…

Materials Science · Physics 2021-06-29 Manish Anand

We study the effects of the magnetic field on the relaxation of the magnetization of small monodomain non-interacting particles with random orientations and distribution of anisotropy constants. Starting from a master equation, we build up…

Materials Science · Physics 2016-08-16 Oscar Iglesias , Amílcar Labarta

We derive a simple system of equations to describe the magnetization relaxation of a molecular spin in weak interaction with a thermal bath for the whole temperature domain. Using this for the intermediate temperature domain where the…

Materials Science · Physics 2022-12-27 Le Tuan Anh Ho , Liviu Ungur , Liviu F. Chibotaru

We reported a systematic change in the average magnetic relaxation rate, after the application and removal of a 5 T magnetic field, in a polycrystalline sample of La0.5Ca0.5MnO3. Magnetic relaxation measurements and magnetization versus…

Strongly Correlated Electrons · Physics 2009-10-31 J. Lopez , P. N. Lisboa-Filho , W. A. C. Passos , W. A. Ortiz , F. M. Araujo-Moreira

Brownian relaxation is one of the primary mechanisms that allows magnetic nanoparticles (MNPs) to convert magnetic energy into thermal energy under an excitation magnetic field. Accurately characterizing the MNPs' magnetization dynamics…

Magnetic nanoparticles are useful biological probes as well as therapeutic agents. There have been several approaches used to model nanoparticle magnetization dynamics for both Brownian as well as N\'eel rotation. The magnetizations are…

Mesoscale and Nanoscale Physics · Physics 2015-05-12 Daniel B. Reeves , John B. Weaver

Thermal fluctuations of nanomagnets driven by spin-polarized currents are treated via the Landau-Lifshitz-Gilbert equation as generalized to include both the random thermal noise field and Slonczewski spin-transfer torque terms. The…

Statistical Mechanics · Physics 2017-09-26 Y. P. Kalmykov , D. Byrne , W. T. Coffey , W. J. Dowling , S. V. Titov , J. E. Wegrowe

The investigation of a sizable thermal enhancement of magnetization is put forward for uniaxial ferromagnetic nanoparticles that are placed in a rotating magnetic field. We elucidate the nature of this phenomenon and evaluate the resonant…

Statistical Mechanics · Physics 2016-08-16 S. I. Denisov , T. V. Lyutyy , P. Hänggi

Magnetic nanomaterials record information as fast as picoseconds in computer memories but retain it for millions of years in ancient rocks. This exceedingly broad range of times is covered by hopping over a potential energy barrier through…

Optics · Physics 2023-09-12 S. Adhikari , Y. Wang , P. Spaeth , F. Scalerandi , W. Albrecht , J. Liu , M. Orrit

Spin relaxation between the two lowest-lying spin-states has been studied in the S=4 single molecule magnet Ni$_4$ under steady state conditions of low amplitude and continuous microwave irradiation. The relaxation rate was determined as a…

Mesoscale and Nanoscale Physics · Physics 2008-07-22 G. de Loubens , D. A. Garanin , C. C. Beedle , D. N. Hendrickson , A. D. Kent

In spin values the damping parameters of the free layer are determined non-locally by the entire magnetic configuration. In a dual spin valve structure that comprises a free layer embedded between two pinned layers, the spin pumping…

Mesoscale and Nanoscale Physics · Physics 2011-11-07 Xuhui Wang , Aurelien Manchon

We investigate the effect of anisotropy and weak dipolar interactions on the magnetization of an assembly of nanoparticles with distributed magnetic moments, i.e., assembly of magnetic nanoparticles in the one-spin approximation, with…

Statistical Mechanics · Physics 2009-11-11 H. Kachkachi , M. Azeggagh

We use a single dipole approximation to analyze the behavior of anisotropy-dominated magnetic nanoparticles subjected to an external r.f. field. We identify the steady state oscillations and analyze their stability. We also analyze the case…

Materials Science · Physics 2009-11-13 K. Rivkin , W. Saslow , J. Ketterson

The effect of long range dipole-dipole interactions on the thermal fluctuations of the magnetization of an assembly of single-domain ferromagnetic particles is considered. If orientational correlations between the particles are neglected,…

Statistical Mechanics · Physics 2019-02-05 Pierre-Michel Déjardin

We present an extensive study of the time dependence of the magnetization in a polycrystalline and low temperature charge ordered La0.5Ca0.5MnO3 sample. After application and removal of a 5 T magnetic field, a systematic variation of the…

Strongly Correlated Electrons · Physics 2007-05-23 J. Lopez , P. N. Lisboa-Filho , W. A. C. Passos , W. A. Ortiz , F. M. Araujo-Moreira

The magnetization reversal in a single molecular magnet (SMM) weakly coupled to an electrode with spin-dependent splitting of chemical potentials (spin bias) is theoretically investigated by means of the rate equation. A microscopic…

Mesoscale and Nanoscale Physics · Physics 2009-05-14 Hai-Zhou Lu , Bin Zhou , Shun-Qing Shen

We utilize a hybrid quantum-classical equation of motion approach to investigate the spin dynamics and spin-transfer torque in a spin valve under bias voltage. We show that the interplay between localized classical magnetic moments and…

Mesoscale and Nanoscale Physics · Physics 2022-11-28 Rudolf Smorka , Pavel Baláž , Michael Thoss , Martin Žonda

We describe an experiment aimed at measuring the spin dynamics of the Fe8 single-molecule magnet in the presence of pulsed microwave radiation. In earlier work, heating was observed after a 0.2-ms pulse of intense radiation, indicating that…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 M. Bal , Jonathan R. Friedman , M. T. Tuominen , E. M. Rumberger , D. N. Hendrickson

We present numerical and analytical results for the swiching times of magnetic nanoparticles with uniaxial anisotropy at elevated temperatures, including the vicinity of T_c. The consideration is based in the Landau-Lifshitz-Bloch equation…

Statistical Mechanics · Physics 2007-05-23 D. A. Garanin , O. Chubykalo-Fesenko

The magnetic behavior of truncated conical nanoparticles in patterned thin films is investigated as a function of their size and shape. Using a scaling technique, phase diagrams giving the relative stability of characteristic internal…

Mesoscale and Nanoscale Physics · Physics 2011-06-16 J. Escrig , P. Landeros , J. C. Retamal , D. Altbir , J. d'Albuquerque e Castro