相关论文: Superparamagnetic behaviour of antiferromagnetic D…
We report a systematic study on the structural and magnetic properties of Co_{x}Fe_{3-x}O_{4} magnetic nanoparticles with sizes between $5$ to $25$ nm, prepared by thermal decomposition of Fe(acac)_{3} and Co(acac)_{2}. The large…
The polar states of uniaxial ferroelectric nanoparticles interacting with a surface system of electronic and ionic charges with a broad distribution of mobilities is explored, which corresponds to the experimental case of nanoparticles in…
We propose a simple and solvable mean-field model of the scattering of transverse optic modes by Polarized Nano Regions (PNR) in the paraelectric phase of relaxor ferroelectrics. The PNR is assumed to be a ferroelectric sphere embedded in…
Louis Neel pointed out in his Nobel lecture that while abundant and interesting from a theoretical viewpoint, antiferromagnets did not seem to have any applications. Indeed, the alternating directions of magnetic moments on individual atoms…
The impurity-induced antiferromagnetic ordering of the doped Haldane magnet Pb(Ni{1-x}Mg{x})2V2O8 (0 < x <0.06) was studied by electron spin resonance (ESR) on ceramic samples in the frequency range 9-110 GHz. Below the N\'{e}el temperature…
We report nuclear magnetic resonance measurements of the spin-1/2 anisotropic triangular lattice antiferromagnet Cs$_2$CuCl$_4$ as a function of temperature and applied magnetic field. The observed temperature and magnetic field dependence…
We report on the thermoelectric power $S(T)$, electrical resistivity and thermal conductivity measurements on the antiferromagnetic CeCoAl$_4$ compound. The N\'eel temperature of CeCoAl$_4$ is $T_N$=13.5K and a metamagnetic-like transition…
We show that in the severe slowing down temperature regime the relaxation of antiferromagnetic rings and similar magnetic nanoclusters is governed by the quasi-continuum portion of their quadrupolar fluctuation spectrum and not by the…
We report studies on temperature, field and time dependence of magnetization on cupric oxide nanoparticles of sizes 9 nm, 13 nm and 16 nm. The nanoparticles show unusual features in comparison to other antiferromagnetic nanoparticle…
This work focuses on the microstructure, magnetic properties and magnetocaloric effect of CoFe$_2$O$_4$ (CFO) nanoparticles elaborated by sol-gel auto combustion method. The XRD investigation indicates that CFO is crystallized in a cubic…
Inelastic neutron scattering is used to investigate the collective magnetic excitations of the high-temperature superconductor parent antiferromagnet La2CuO4. We find that while the lower energy excitations are well described by spin-wave…
The dielectric properties of Fe$_{3}$O$_{4}$ magnetic nanoparticles with an insulating coating layer of SiO$_{2}$ were investigated. At high temperatures, the changes of the dielectric constant and loss induced by the magnetic field are…
The proton hyperfine shift K and NMR relaxation rate $1/T_1$ have been measured as a function of temperature in the S=1/2 Heisenberg antiferromagnetic ladder Cu2(C5H12N2)2Cl4. The presence of a spin gap $\Delta \simeq J_\perp-J_\parallel$…
The A-site spinel material, CoAl2O4, is a physical realization of the frustrated diamond-lattice antiferromagnet, a model in which is predicted to contain unique incommensurate or `spin-spiral liquid' ground states. Our previous…
We report static and dynamic properties of the antiferromagnetic compound Zn$_{2}$(VO)(PO$_{4}$)$_{2}$, and the consequences of non-magnetic Ti$^{4+}$ doping at the V$^{4+}$ site. $^{31}$P nuclear magnetic resonance (NMR) spectra and…
Each single domain nano-magnet acts as a magnetic dipole in addition it oscillates its magnetization about the easy axis and rotates coherently depending upon temperature and anisotropy. In an ensemble of nano-magnets, the relaxation time…
We have performed an inelastic neutron scattering study of the low energy spin dynamics of the heavy fermion compound Ce0.8La0.2Al3 as a function of temperature and external pressure up to 5 kbar. At temperatures below 3 K, the magnetic…
Films of metal-insulator nanogranular composites M$_x$D$_{100-x}$ with different composition and percentage of metal and dielectric phases (M = Fe, Co, CoFeB; D = Al$_2$O$_3$, SiO$_2$, LiNbO$_3$; x $\approx$ 15-70 at.%) are investigated by…
Inelastic neutron scattering measurements on single crystals of superconducting BaFe1.84Co0.16As2 reveal a magnetic excitation located at wavevectors (1/2 1/2 L) in tetragonal notation. On cooling below TC, a clear resonance peak is…
For superparamagnetic nanoparticles (SMNPs), it is often claimed that the rapid thermal fluctuations of their magnetic moments negates the magnetic dipolar attraction, hence preventing aggregation in liquid suspension. However we find that…