相关论文: Magnetic resonance in nanoparticles: between ferro…
The scope of this article is to report very detailed results of the measurements of magnetic relaxation phenomena in the new Cu$_{0.5}$Fe$_{2.5}$O$_{4}$ nanoparticles and known CuFe$_{2}$O$_{4}$ nanoparticles. The size of synthesized…
We demonstrate a technique that enables ferromagnetic resonance (FMR) measurements of the normal modes for magnetic excitations in individual nanoscale ferromagnets, smaller in volume by a factor of 1000 than can be probed by other methods.…
Antiferromagnetic resonance in a bulk $\alpha$-MnTe crystal is investigated using both frequency-domain and time-domain THz spectroscopy techniques. At low temperatures, an excitation at the photon energy of $(3.5\pm 0.1)$~meV is observed…
Using a `standard' NMR spin-echo technique we determined the spin polarization of two-dimensional electrons, confined to GaAs quantum wells, from the hyperfine shift of Ga nuclei in the wells. Concentrating on the temperature and magnetic…
The local magnetic field in a Penning-Malmberg trap is found by measuring the temperatures that result when electron plasmas are illuminated by microwaves pulses. Multiple heating resonances are observed as the pulse frequencies are swept.…
Magnetic excitations of the exchange-dipole quasi 1D XXZ antiferromagnet are studied in the ordered phase. We observe a transformation of the electron spin resonance (ESR) spectrum when crossing the N\'{e}el temperature near 0.2 K. The…
We present a detailed study of the magnetic behavior of iron-oxide (gamma-Fe2O3 and Fe3O4) nanoparticles constituents of ferrofluids (FF's) with average particle sizes <d> = 2.5 and 10 nm. The particles were dispersed in the frozen liquid…
We calculate the mesoscopic fluctuations of the magnetic anisotropy of ferromagnetic nanoparticles. A microscopic spin-orbit Hamiltonian considered as a perturbation of the much stronger exchange interaction first yields an explicit…
ZnO nanoparticles with Wurtzite structure were prepared by chemical methods at low temperature in aqueous solution. Nanoparticles are in the range from about 10 to 30 nm. Ferromagnetic properties were observed from 2 K to room temperature…
The dynamic magnetic properties of Ni nanoparticles diluted in an amorphous SiO2 matrix prepared from a modified sol-gel method have been studied by the frequency f dependence of the ac magnetic susceptibility \c{hi}(T). For samples with…
Inelastic neutron scattering experiments have been performed on single crystals of Nd$_{1-x}$Sr$_{x}$MnO$_{3}$ with x$\approx$0.5. Colossal magnetoresistance (CMR) in the manganites arises from the interplay between a ferromagnetic metallic…
The rotational dynamics of magnetic nano particles in rotating magnetic fields in the presence of thermal noise is studied both theoretically and by performing numerical calculations. Kinetic equations for the dynamics of particles with…
We have studied the magnetic and power absorption properties of three samples of CoFe2O4 nanoparticles with sizes from 5 to 12 nm prepared by thermal decomposition of Fe (acac)3 and Co(acac)2 at high temperatures. The blocking temperatures…
Antiferromagnetic spintronics is an emerging field; antiferromagnets can improve the functionalities of ferromagnets with higher response times, and having the information shielded against external magnetic field. Moreover, a large list of…
We investigate the magnetization dynamics of ferromagnetic nanoparticles in the atomistic approach taking account of surface anisotropy and the spin misalignment it causes. We demonstrate that such inhomogeneous spin configurations induce…
Static and dynamic properties of magnetically soft amorphous ferromagnets have been studied analytically and numerically within random-field and random-anisotropy models. External field and coherent anisotropy that are weak compared to…
We report muon-spin rotation, heat capacity, magnetization, and ac magnetic susceptibility measurements of the layered spin-1/2 antiferromagnet NaNiO2. These show the onset of long-range magnetic order below T_N = 19.5K. Rapid muon…
We present a review of recent advances in the study of many-body effects in magnetic nanoparticles. Considering classical spins on a lattice coupled by the exchange interaction in the presence of the bulk and surface anisotropy, we…
The structural and magnetic properties of ZnFe2O4 nanoparticles embedded in a non-magnetic ZnO matrix are presented. X-ray diffractograms and Transmission Electron Microscopy (TEM) images showed that the resulting samples are composed of…
A study of spherical maghemite nanoparticles on a two dimensional triangular array was carried out using a stochastic Landau-Lifshitz-Gilbert (sLLG) approach. The simulation method was first validated with a triangular array of simple…