相关论文: Particle size dependence of magnetization and non-…

Using high resolution powder x-ray and neutron diffraction experiments, we determined the off-centered displacement of the ions within a unit cell and magnetoelectric coupling in nanoscale BiFeO$_3$ ($\approx$20-200 nm). We found that both…

We report results of a comprehensive study of the phase transition at T_N (~643 K) as a function of particle size in multiferroic BiFeO3 system. We employed electrical, thermal, and temperature dependent X-ray diffraction (XRD) studies in…

Improvement in magnetic and electrical properties of multiferroic BiFeO$_3$ in conjunction with their dependence on particle size is crucial due to its potential applications in multifunctional miniaturized devices. In this investigation,…

Using the results of x-ray and neutron diffraction experiments, we show that the ferroelectric polarization, in ~22 nm particles of BiFeO3, exhibits a jump by ~30% around the magnetic transition point T_N (~635 K) and a suppression by ~7%…

First- and second-harmonic dielectric susceptibilities are maidenly studied on Samarium Orthoferrite of mesoscopic/500 nm and nanoscopic/55 nm grainsizes. Magneto-electrically coupled to the antiferromagnetic and spin-reorientation…

Bismuth ferrite (BiFeO3) is one of the most promising multiferroics with a sufficiently high ferroelectric (FE) and antiferromagnetic transition temperatures, and magnetoelectric (ME) coupling coefficient at room temperature, and thus it is…

A remarkably high saturation magnetization of ~0.4mu_B/Fe along with room temperature ferromagnetic hysteresis loop has been observed in nanoscale (4-40 nm) multiferroic BiFeO_3 which in bulk form exhibits weak magnetization (~0.02mu_B/Fe)…

Magnetization of antiferromagnetic nanoparticles is known to generally scale up inversely to their diameter (d) according to N\'eel's model. Here we report a deviation from this conventional linear 1/d dependence, altered significantly by…

Electron microdiffraction study of phase transition in La2/3Ca1/3MnO3 revealed temperature dependent (h+1/2,0,l) diffraction spots. Their intensity peaks at Tc. Quantitative electron diffraction intensity analysis shows that they come from…

In transition metal oxides, quantum confinement arising from a large surface to volume ratio often gives rise to novel physico-chemical properties at nanoscale. Their size dependent properties have potential applications in diverse areas,…

We synthesized and characterized the colloidal suspensions of $FeO \cdot Fe_{(2-x)}Nd_{x}O_{3}$ nanoparticles with $x=0.00, 0.02, 0.04, 0.06 \text{ and }0.1.$ The effect of the $Fe^{3+}$ ion replacement by $Nd^{3+}$ on the crystal structure…

Nd_0.5 Ca_0.5 MnO_3 (NCMO) nanoparticles (average diameter ~ 20 and 40 nm) are synthesized by polymeric precursor sol-gel method and characterized by X- ray diffraction, transmission electron microscopy (TEM), selective area electron…

Transport and magnetic properties have been studied in two sets of sol-gel prepared Pr$_{1/2}$Sr$_{1/2}$MnO$_{3}$ nanoparticles having average particle size of 30 nm and 45 nm. Our measurements suggest that the formation of charge ordered…

Co2FeAl (CFA) nanoparticles (NPs) of different sizes were synthesized by chemical route. The effect of the size of NPs upon the structure and magnetization compared to its bulk counterpart was investigated. The structure and composition…

We present X-ray diffraction (XRD), M\"ossbauer spectroscopy (MS) and d.c. magnetization measurements performed on ball-milled CuFe2O4 samples. The average particle size <d> was found to decrease to the nanometer range after t=15 min of…

We report the results of direct measurement of remanent hysteresis loops on nanochains of BiFeO$_3$ at room temperature under zero and $\sim$20 kOe magnetic field. We noticed a suppression of remanent polarization by nearly $\sim$40\% under…

Magnetization reversal of individual, isolated high-aspect-ratio Fe nanoparticles with diameters comparable to the magnetic exchange length is studied by high-sensitivity submicron Hall magnetometry. For a Fe nanoparticle with diameter of 5…

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…

When decreasing the size of nanoscale magnetic particles their magnetization becomes vulnerable to thermal fluctuations as approaching the superparamgnetic limit, hindering thus applications relying on a stable magnetization. Here, we show…

In this investigation, Gd and Mn co-doped Bi$_{0.85}$Gd$_{0.15}$Fe$_{1-x}$Mn$_x$O$_3$ (x=0.0-0.15) nanoparticles have been prepared to report the influence of co-substitution on their structural, optical, magnetic and electrical properties.…