Related papers: Comment on "Memory Effects in an Interacting Magne…
Recently, Sun et al reported that striking memory effects had been clearly observed in their new experiments on an interacting nanoparticle system [1]. They claimed that the phenomena evidenced the existence of a spin-glass-like phase and…
In Phys. Rev. Lett. 91 167206 (2003), Sun et al. study memory effects in an interacting nanoparticle system with specific temperature and field protocols. The authors claim that the observed memory effects originate from spin-glass dynamics…
We have performed a series of measurements on the low temperature behavior of a magnetic nano-particle system. Our results show striking memory effects in the dc magnetization. Dipolar interactions among the nano-particles {\em suppress}…
We study magnetic relaxation dynamics, memory and aging effects in interacting polydisperse antiferromagnetic NiO nanoparticles by solving a master equation using a two-state model. We investigate the effects of interactions using dipolar,…
The role of dipolar interactions among Ni nanoparticles (NP) embedded in an amorphous SiO2/C matrix with different concentrations has been studied performing ac magnetic susceptibility Chi_ac measurements. For very diluted samples, with Ni…
A general method for the quantification of dipolar interactions in assemblies of nanoparticles has been developed from a model sample constituted by magnetite nanoparticles of 5 nm in diameter, in powder form with oleic acid as a surfactant…
Memory effects are ubiquitous in nature and are particularly relevant at the nanoscale where the dynamical properties of electrons and ions strongly depend on the history of the system, at least within certain time scales. We review here…
We investigate slow dynamics of collection of a few antiferromagnetic NiO nanoparticles. The zero-field cooled magnetization exhibits size dependent fluctuations. We find memory effects in field cooled magnetization, as well as aging…
The dielectric properties of MnFe$_2$O$_4$ and $\gamma$-Fe$_2$O$_3$ magnetic nanoparticles embedded in insulating matrices were investigated. The samples showed frequency dependent dielectric anomalies coincident with the magnetic blocking…
We report the magnetic properties of magnetic nano-composite, consisting of different quantity of NiFe2O4 nanoparticles in polymer matrix. The nanoparticles exhibited a typical magnetization blocking, which is sensitive on the variation of…
The physical properties of magnetic nanoparticles have been investigated with focus on the influence of dipolar interparticle interaction. For weakly coupled nanoparticles, thermodynamic perturbation theory is employed to derive analytical…
We report studies on magnetization dynamics in NiO nanoparticles of average size 5 nm. Temperature and time dependence of dc magnetization, wait time dependence of magnetic relaxation (aging) and memory phenomena in the dc magnetization are…
Assemblies of magnetic nanoparticles exhibit interesting physical properties arising from the competition of intraparticle dynamics and interparticle interactions. In ordered arrays of magnetic nanoparticles magnetostatic interparticle…
In this paper, effect of dipole-dipole interactions on nonlinear optical properties of the system of randomly located semiconductor nanoparticles embedded in bulk dielectric matrix is investigated. This effect results from the nonzero…
Evidence for the suppression of collective magnetic behavior of dipolarly interacting Fe nanoparticles is found in Fe-Ag granular multilayers. Interaction of Fe particles located in neighboring Fe layers is studied as a function of the…
Magnetic and NMR relaxivity properties of {\gamma}-Fe2O3 nanoparticles embedded into the walls of polyelectrolyte multilayer capsules and freely dispersed in a sodium borate buffer solution have been investigated. The different geometric…
We explore the influence of demagnetization interaction on magnetic memory effect by varying organization geometry of anisotropic ZnFe$_2$O$_4$ nanoparticles in an ensemble. The static and dynamic behaviour of two differently organized…
The energy barrier distribution Eb of five samples with different concentrations x of Ni nanoparticles using scaling plots from ac magnetic susceptibility data has been determined. The scaling of the imaginary part of the susceptibility…
Crystalline Mn5Ge3 nanomagnets are formed inside a Mn-diluted Ge matrix using Mn ion implantation. A temperature-dependent memory effect and slow magnetic relaxation are observed below the superparamagnetic blocking temperature of Mn5Ge3.…
This article reports dependence of exchange bias (EB) effect on interparticle interactions in nanocrystalline Co/CoO core/shell structures, synthesized using conventional sol-gel technique. Analysis via powder X-Ray diffraction (PXRD)…