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Related papers: Unusual superparamagnetic behavior of Co3O4 nanopa…

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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…

Nanoparticles (size 20, 40 and 60 nm) of Pr_0.5Sr_0.5MnO_3 are prepared by sol-gel technique and their magnetic properties are studied using ferromagnetic resonance and magnetization measurements. A comparison with the properties of the…

Strongly Correlated Electrons · Physics 2007-06-13 S. S. Rao , S. V. Bhat

The relation of the magnetically dead layer and structural defects in ultrafine interacting NiFe2O4 nanoparticles (<d> = 4 nm) have been investigated using transmission electron microscopy, X-ray diffraction, ^57Fe M\"ossbauer spectroscopy,…

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…

Strongly Correlated Electrons · Physics 2019-10-01 Aquil Ahmad , Srimanta Mitra , S. K. Srivastava , A. K. Das

We report the observation of positive magnetization on field cooling (PMFC) in low applied magnetic fields (H < 100 Oe) in a single crystal of Ca(3)Rh(4)Sn(13) near its superconducting transition temperature (T(c) approx 8.35 K). For 30 Oe…

We have investigated the magnetic behavior of the nano crystals, synthesized by high-energy ball-milling, for a well-known geometrically frustrated spin-chain system, Ca3CoRhO6, and compared its magnetic characteristics with those of the…

Strongly Correlated Electrons · Physics 2015-05-13 Niharika Mohapatra , Kartik K Iyer , B. A. Chalke , E. V. Sampathkumaran

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…

Materials Science · Physics 2011-03-18 C. -C. Chang , L. Zhao , M. -K. Wu

We report the temperature and field dependence of dc magnetization on sol-gel prepared nanoparticles of Ni(OH)_2. At higher temperature the system is found to behave as a paramagnet while we find evidence for superparamagnetic blocking at…

Mesoscale and Nanoscale Physics · Physics 2007-07-26 S. D. Tiwari , K. P. Rajeev

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…

Materials Science · Physics 2016-08-31 Petra E. Jönsson

In this work we report a study of the magnetic behavior of ferrimagnetic oxide CoFe2O4 and ferrimagnetic oxide/ferromagnetic metal CoFe2O4/CoFe2 nanocomposites. The latter compound is a good system to study hard ferrimagnet/soft ferromagnet…

We report on the low-temperature magnetic ac-susceptibility of antiferromagnetic DyPO4 nanoparticles with a very high surface to volume ratio. The results are interpreted in terms of superparamagnetic relaxation of the Neel vector arising…

Materials Science · Physics 2007-05-23 T. G. Sorop , M. Evangelisti , M. Haase , L. J. de Jongh

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 report specific heat ($C$) and magnetization ($M$) of single crystalline Ce$_4$Pt$_{12}$Sn$_{25}$ at temperature down to $\sim$50mK and in fields up to 3T. $C/T$ exhibits a sharp anomaly at 180mK, with a large $\Delta…

We present a systematic study of core-shell Au/Fe_3O_4 nanoparticles produced by thermal decomposition under mild conditions. The morphology and crystal structure of the nanoparticles revealed the presence of Au core of <d> = (6.9\pm 1.0)…

We report magnetostatic measurements for granulated films (CoFeB)$_{x}$-(SiO$_{2}$)$_{1-x}$ with fabrication induced intraplanar anisotropy. The measurements have been performed in the film plane in the wide temperature interval…

Mesoscale and Nanoscale Physics · Physics 2008-09-23 A. A. Timopheev , S. M. Ryabchenko , V. M. Kalita , A. F. Lozenko , P. A. Trotsenko , V. A. Stephanovich , A. M. Grishin , M. Munakata

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 study the magnetic properties of single crystals of rutile TiO2 implanted with cobalt for various fluences. The temperature variation of zero field cooled(ZFC) and field cooled (FC) magnetization shows a much higher blocking temperature…

Materials Science · Physics 2017-03-16 Shalik Ram Joshi , B. Padmanabhan , Anupama Chanda , N. Shukla , Vivek Malik , D. Kanjilal , Shikha Varma

Magnetic nanoparticles of La0.67Sr0.33MnO3 (LSMO) manganite with mean particle sizes of 13, 16, 18 and 21 nm were prepared by the sol-gel method. The crystal structure and mean particle size of the synthesized powders were estimated by…

Mesoscale and Nanoscale Physics · Physics 2009-07-17 Ali Rostamnejadi , Hadi salamati , Parviz Kameli

Paramagnetic (PM) properties of columnar cobaltosic oxide (Co3O4) nanoparticles, about 75 nm in diameter, have been investigated by magnetization measurements at T > TN = 39 K. In zero or low applied field, the effective PM moment per…

Materials Science · Physics 2015-05-19 Weimeng Chen , Chinping Chen , Lin Guo

8~nm epsilon-Fe2O3 nanoparticles exhibit a spin reorientation transition that begins at 150 K which is a hallmark of this unique iron-oxide polymorph. We find that the change from the high to low temperature magnetic structures has been…

Mesoscale and Nanoscale Physics · Physics 2019-10-02 Richard Jones , Rachel Nickel , Palash K. Manna , J. Hilman , Johan van Lierop