6533b861fe1ef96bd12c58f1
RESEARCH PRODUCT
Coupled stochastic dynamics of magnetic moment and anisotropy axis of a magnetic nanoparticle
Andrejs CēbersR. Taukulissubject
Magnetic Resonance SpectroscopyBiophysicsMetal NanoparticlesBiocompatible Materials02 engineering and technology01 natural sciencesMagneticsParamagnetismNuclear magnetic resonanceMaterials Testing0103 physical sciencesNanotechnology010306 general physicsPhysicsStochastic ProcessesModels StatisticalCondensed matter physicsMagnetic energyMagnetic momentDemagnetizing field021001 nanoscience & nanotechnologyElectron magnetic dipole momentMagnetic susceptibilityMagnetic anisotropyAnisotropy0210 nano-technologyMagnetic dipoleAlgorithmsdescription
An algorithm is developed for numerical simulation of coupled stochastic dynamics of magnetic moment and magnetic anisotropy axis of a nanoparticle. Time-correlation functions of the magnetic moment and its components longitudinal and transverse to the magnetic anisotropy axis are calculated by averaging along the stochastic trajectory. The longitudinal and transverse relaxation times are found by fitting the time correlation functions. Existing theoretical relations derived by the effective field approach in the limit of small fields are confirmed. The time-correlation functions of magnetic moments of nanoparticles in dependence on their properties are calculated numerically for arbitrary large magnetic fields and it is shown that they may be approximated by a sum of several exponentials. These results are applied for the calculation of relaxivity parameters of nuclear magnetic resonance (NMR) imaging in dependence on the field strength.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2012-12-14 | Physical Review E |