Hysteretic giant magnetoimpedance effect analyzed by first-order reversal curves

Hysteretic giant magnetoimpedance (GMI) of amorphous ribbons with a well-defined transversal domain structure is investigated by means of first-order reversal curves (FORC) analysis. The FORCs are not confined to the hysteretic area, exceeding the major curve amplitude. Irreversible switches of the transverse permeability, caused by domain wall structure transitions, may be the origin of the observed FORC distribution. An interlinked hysteron/anti-hysteron model is proposed to interpret it, which allows analyzing the influence of frequency and magnetostriction upon the hysteretic GMI effect.Comment: 19 pages, 9 figure

Synthesis Of Ag-cofe2o4 Dimer Colloidal Nanoparticles And Enhancement Of Their Magnetic Response

This paper reports the structural and magnetic properties of Ag-CoFe 2O4 colloidal dimer nanoparticles (NPs) synthesized using a two-step solution-phase route. Ag NPs were used as seeds to grow Ag-CoFe 2O4 dimer NPs using thermal decomposition of metallic precursor. By means of temperature and field dependent dc magnetization measurements, it is found that the silver due to its interface with CoFe 2O4 particles leads to thermal stabilization of the dimer NPs superior as compared to CoFe2O4 alone. Our results show enhancement of the magnetic anisotropy and a large coercivity at 2 K for dimer NPs, which could be ascribed to interface effect between Ag and CoFe 2O4 components and the related structural defects. © 2011 American Institute of Physics.1097Sun, Y., Xia, Y., Shape-controlled synthesis of gold and silver nanoparticles (2002) Science, 298 (5601), pp. 2176-2179. , DOI 10.1126/science.1077229Wang, C., Wei, Y., Jiang, H., Sun, S., (2009) Nano Lett., 9, p. 4544. , 10.1021/nl903077tLopes, G., Vargas, J.M., Sharma, S.K., Beron, F., Pirota, K.R., Knobel, M., Rettori, C., Zysler, R.D., (2010) J. Phys. Chem. C, 114, p. 10148. , 10.1021/jp102311uHori, H., Yamamoto, Y., Ywamoto, T., Miura, T., Teranishi, T., Miyake, M., (2004) Phys. Rev. B, 69, p. 174411. , 10.1103/PhysRevB.69.174411Jordan, A., Scholz, R., Wust, P., Fahling, H., Felix, R., (1999) J. Magn. Magn. Mater., 201, p. 413. , 10.1016/S0304-8853(99)00088-8Goya, G.F., Grazu, V., Ibarra, M.R., Magnetic nanoparticles for cancer therapy (2008) Current Nanoscience, 4 (1), pp. 1-16. , http://www.ingentaconnect.com/content/ben/cnano/2008/00000004/00000001/ art00001, DOI 10.2174/157341308783591861Yu, H., Chen, M., Rice, P.M., Wang, S.X., White, R.L., Sun, S., Dumbbell-like bifunctional Au-Fe3O4 nanoparticles (2005) Nano Letters, 5 (2), pp. 379-382. , DOI 10.1021/nl047955qPeddis, D., Cannas, C., Piccaluga, G., Agostinelli, E., Fiorani, D., (2010) Nanotechnology, 21, p. 125705. , 10.1088/0957-4484/21/12/125705Desjonquéres, M.C., Barreteau, C., Autés, G., Spanjaard, D., (2007) Phys. Rev. B, 76, p. 024412. , 10.1103/PhysRevB.76.024412Salazar-Alvarez, G., Olsson, R.T., Sort, J., Macedo, W.A.A., Ardisson, J.D., Baro, M.D., Gedde, U.W., Nogues, J., Enhanced coercivity in co-rich near-stoichiometric CoxFe 3-xO4+δ nanoparticles prepared in large batches (2007) Chemistry of Materials, 19 (20), pp. 4957-4963. , DOI 10.1021/cm070827

Frequency Dependence Of The Magnetoimpedance In Amorphous Cop Electrodeposited Layers

Magnetic properties and changes of impedance upon external field (MI) are studied in amorphous CoP magnetic layers obtained by galvanostatic electrodeposition over cylindrical Cu substrates. The magnetic layer thickness is controlled by deposition time and varies between 3 and 7 μm. Due to the columnar growth of Co, thicker layers have stronger perpendicular radial anisotropy. The field and frequency dependence of the impedance is measured in the kHz/MHz range. Although it is generally accepted that a radial anisotropy should be unfavorable to the MI effect, an increase of the MI ratio with the thickness of the magnetic layer, and thus with anisotropy, is observed. Results are explained in terms of a model considering the current distribution along the sample thickness with two well-defined regions having different transport and magnetic properties. © 2000 American Institute of Physics.879 II48254827Landau, L.D., Lifshitz, E.M., (1975) Electrodynamics of Continuous Media, p. 195. , Pergamon, OxfordPanina, L.V., Mohri, K., Uchiyama, T., Noda, M., (1995) IEEE Trans. Magn., 31, p. 1249Beach, R.S., Berkowitz, A.E., (1994) Appl. Phys. Lett., 64, p. 3652Rao, K.V., Humphrey, F.B., Costa-Kramër, J.L., (1994) J. Appl. Phys., 76, p. 6204Knobel, M., Sánchez, M.L., Velázquez, J., Vázquez, M., (1995) J. Phys.: Condens. Matter, 7, pp. L-115Sommer, R.L., Chien, C.L., (1995) Appl. Phys. Lett., 67, p. 3346Panina, L.V., Mohri, K., (1996) J. Magn. Magn. Mater., 157-158, p. 137Vázquez, M., Zhukov, A.P., Aragoneses, P., Arcas, J., García-Beneytez, J.M., Marin, P., Hernando, A., IEEE Trans. Magn., , in pressBeach, R.S., Smith, N., Platt, C.L., Jeffers, F., Berkowitz, A.E., (1996) Appl. Phys. Lett., 68, p. 2753Usov, N., Antonov, A., Granovsky, A., (1997) J. Magn. Magn. Mater., 171, p. 64Favieres, C., Aroca, C., Sánchez, M.C., Rao, K.V., Madurga, V., (1998) J. Magn. Magn. Mater., 177-181, p. 107Vázquez, M., Sinnecker, J.P., Kurlyandskaya, G.V., (1999) Mater. Sci. Forum, 302-303, p. 209Sinnecker, J.P., Knobel, M., Sartorelli, M.L., Schonmaker, J., Silva, F.C.S., (1998) J. Phys. IV, 8 (PR2), p. 665Machado, F.L.A., Rodrigues, A.R., Puça, A.A., De Araujo, A.E.P., (1999) Mat. Sci. Forum, 302-303, p. 202Cargil III, G.S., Gambino, R.J., Cuomo, J.J., (1974) IEEE Trans. Magn., MAG-10, p. 803Dietz, G., Bestgen, H., Hungenberg, J., (1978) J. Magn. Magn. Mater., 9, p. 208Riveiro, J.M., Sánchez-Trujillo, M.C., (1980) IEEE Trans. Magn., MAG-16, p. 1426Luborsky, F.E., (1983) Amorphous Metallic Alloys, , Butterworths, LondonMénard, D., Britel, M., Ciureanu, P., Yelon, A., (1998) J. Appl. Phys., 84, p. 2805Kraus, L., (1999) J. Magn. Magn. Mater., 195, p. 764Yelon, A., Ménard, D., Britel, M., Ciureanu, P., (1996) Appl. Phys. Lett., 69, p. 308

Compact Ag@fe3o4 Core-shell Nanoparticles By Means Of Single-step Thermal Decomposition Reaction

A temperature pause introduced in a simple single-step thermal decomposition of iron, with the presence of silver seeds formed in the same reaction mixture, gives rise to novel compact heterostructures: brick-like Ag@Fe3O4 core-shell nanoparticles. This novel method is relatively easy to implement, and could contribute to overcome the challenge of obtaining a multifunctional heteroparticle in which a noble metal is surrounded by magnetite. Structural analyses of the samples show 4 nm silver nanoparticles wrapped within compact cubic external structures of Fe oxide, with curious rectangular shape. The magnetic properties indicate a near superparamagnetic like behavior with a weak hysteresis at room temperature. The value of the anisotropy involved makes these particles candidates to potential applications in nanomedicine.4Brown, M.A., Effects of the operating magnetic field on potential nmr contrast agents (1985) Magn. Reson. 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Nanometric Particle Size And Phase Controlled Synthesis And Characterization Of γ-fe2o3 Or (α + γ)-fe2o3 By A Modified Sol-gel Method

Fe2O3 nanoparticles with sizes ranging from 15 to 53 nm were synthesized by a modified sol-gel method. Maghemite particles as well as particles with admixture of maghemite and hematite were obtained and characterized by XRD, FTIR, UV-Vis photoacoustic and Mössbauer spectroscopy, TEM, and magnetic measurements. The size and hematite/maghemite ratio of the nanoparticles were controlled by changing the Fe:PVA (poly (vinyl alcohol)) monomeric unit ratio used in the medium reaction (1:6, 1:12, 1:18, and 1:24). The average size of the nanoparticles decreases, and the maghemite content increases with increasing PVA amount until 1:18 ratio. The maghemite and hematite nanoparticles showed cubic and hexagonal morphology, respectively. Direct band gap energy were 1.77 and 1.91 eV for A6 and A18 samples. Zero-field-cooling-field-cooling curves show that samples present superparamagnetic behavior. Maghemite-hematite phase transition and hematite Néel transition were observed near 700 K and 1015 K, respectively. Magnetization of the particles increases consistently with the increase in the amount of PVA used in the synthesis. Mössbauer spectra were adjusted with a hematite sextet and maghemite distribution for A6, A12, and A24 and with maghemite distribution for A18, in agreement with XRD results. © 2013 AIP Publishing LLC.11410Xu, P., Zeng, G.M., Huang, D.L., Feng, C.L., Hu, S., Zhao, M.H., Lai, C., Liu, Z.F., (2012) Sci. Total Environ., 424, pp. 1-10. , 10.1016/j.scitotenv.2012.02.023Rajabi, F., Karimi, N., Saidi, M.R., Primo, A., Varma, R.S., Luque, R., (2012) Adv. Synth. Catal., 354, pp. 1707-1711. , 10.1002/adsc.201100630Kitamuraa, H., Zhaob, L., Hangc, B.T., Okadab, S., Yamaki, J.-I., (2012) J. Power Sources, 208, pp. 391-396. , 10.1016/j.jpowsour.2012.02.051Figuerola, A., Di Corato, R., Manna, L., Pellegrino, T., (2010) Pharmacol. 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Influence of Anodic Conditions on Self-ordered Growth of Highly Aligned Titanium Oxide Nanopores

Self-aligned nanoporous TiO2templates synthesized via dc current electrochemical anodization have been carefully analyzed. The influence of environmental temperature during the anodization, ranging from 2 °C to ambient, on the structure and morphology of the nanoporous oxide formation has been investigated, as well as that of the HF electrolyte chemical composition, its concentration and their mixtures with other acids employed for the anodization. Arrays of self-assembled titania nanopores with inner pores diameter ranging between 50 and 100 nm, wall thickness around 20–60 nm and 300 nm in length, are grown in amorphous phase, vertical to the Ti substrate, parallel aligned to each other and uniformly disordering distributed over all the sample surface. Additional remarks about the photoluminiscence properties of the titania nanoporous templates and the magnetic behavior of the Ni filled nanoporous semiconductor Ti oxide template are also included

Magnetostatic Behaviour Of Antidot Arrays Under The Local Influence Of Nanopillars

We fabricated highly ordered patterned Permalloy nanometric structures by means of ion beam sputtering on top of an anodic aluminium oxide nanoporous template. First-order reversal curve (FORC) results and micromagnetic simulations indicate the presence of Permalloy inside one side of the pores, leading to a nanopillar array anisotropically arranged combined with an antidot array. The strong shape anisotropy of the pillar forces it to maintain the magnetization along its axis, even for a large in-plane applied field. This phenomenon induces out-of-plane hysteresis, as well as in-plane anisotropic behaviour. Depending on the in-plane applied field direction, the presence of nanopillars differently modifies the regular domain pattern, and therefore they could act as a new parameter for tailoring of magnetic anisotropy in antidot arrays. © 2012 IOP Publishing Ltd.4550Allwood, D.A., Xiong, G., Faulkner, C.C., Atkinson, D., Petit, D., Cowburn, R.P., Magnetic domain-wall logic (2005) Science, 309 (5741), pp. 1688-1692. , DOI 10.1126/science.1108813Schneider, T., Serga, A.A., Leven, B., Hillebrands, B., Stamps, R.L., Kostylev, M.P., (2008) Appl. Phys. Lett., 92 (2). , 10.1063/1.2834714 0003-6951 022505Ross, C.A., Smith, H.I., Savas, T., Schattenburg, M., Farhoud, M., Hwang, M., Walsh, M., Ram, R.J., (1999) J. Vac. Sci. Technol., 17 (6), pp. 3168-3176. , 10.1116/1.590974 0734-211X BTopp, J., Podbielski, J., Heitmann, D., Grundler, D., (2008) Phys. Rev., 78 (2). , 10.1103/PhysRevB.78.024431 1098-0121 B 024431Wang, Z.K., Zhang, V.L., Lim, H.S., Ng, S.C., Kuok, M.H., Jain, S., Adeyeye, A.O., (2010) ACS Nano, 4 (2), pp. 643-648. , 10.1021/nn901171u 1936-0851Cowburn, R.P., Adeyeye, A.O., Bland, J.A.C., (1997) Appl. Phys. Lett., 70 (17), pp. 2309-2311. , 10.1063/1.118845 0003-6951Torres, L., Lopez-Diaz, L., Iniguez, J., Micromagnetic tailoring of periodic antidot permalloy arrays for high density storage (1998) Applied Physics Letters, 73 (25), pp. 3766-3768. , DOI 10.1063/1.122888, PII S0003695198040510Yu, T.A., Langford, R.M., Petford-Long, A.K., (2000) Appl. Phys. Lett., 77 (19), pp. 3063-3065. , 10.1063/1.1323737 0003-6951Wang, C.C., Adeyeye, A.O., Singh, N., (2006) Nanotechnology, 17 (6), pp. 1629-1636. , 10.1088/0957-4484/17/6/015 0957-4484Kostylev, M., Gubbiotti, G., Carlotti, G., Socino, G., Tacchi, S., Wang, C., Singh, N., Stamps, R.L., Propagating volume and localized spin wave modes on a lattice of circular magnetic antidots (2008) Journal of Applied Physics, 103 (7), pp. 07C507. , DOI 10.1063/1.2831792Neusser, S., Botters, B., Grundler, D., (2008) Phys. Rev., 78 (5). , 10.1103/PhysRevB.78.054406 1098-0121 B 054406Neusser, S., Botters, B., Becherer, M., Schmitt-Landsiedel, D., Grundler, D., (2008) Appl. Phys. Lett., 93 (12). , 10.1063/1.2988290 0003-6951 122501Neusser, S., Duerr, G., Bauer, H.G., Tacchi, S., Madami, M., Woltersdorf, G., Gubbiotti, G., Grundler, D., (2010) Phys. Rev. Lett., 105 (6). , 10.1103/PhysRevLett.105.067208 0031-9007 067208Masuda, H., Fukuda, K., (1995) Science, 268 (5216), pp. 1466-1468. , 10.1126/science.268.5216.1466 0036-8075Prieto, P., Pirota, K.R., Climent-Font, A., Vazquez, M., Sanza, J.M., (2011) Surf. Interfac. Anal., 43 (11), pp. 1417-1422. , 10.1002/sia.3733 0142-2421Mayergoyz, I.D., (1986) Phys. Rev. Lett., 56 (15), pp. 1518-1521. , 10.1103/PhysRevLett.56.1518 0031-9007Prieto, P., Pirota, K.R., Vazquez, M., Sanza, J.M., (2008) Phys. Stat. Sol., 205 (2), pp. 363-367. , 10.1002/pssa.200723280 1862-6300 APreisach, F., (1935) Z. Phys., 94 (5-6), pp. 277-302. , 10.1007/BF01349418 1434-6001Beron, F., Clime, L., Ciureanu, M., Menard, D., Cochrane, R.W., Yelon, A., Reversible and quasireversible information in first-order reversal curve diagrams (2007) Journal of Applied Physics, 101 (9), pp. 09J107. , DOI 10.1063/1.2712172Béron, F., Pirota, K.R., Vega, V., Prida, V.M., Fernández, A., Hernando, B., Knobel, M., (2011) New J. Phys., 13 (1). , 1367-2630 013035http://mathnistgov/oommf/Béron, F., Clime, L., Ciureanu, M., Cochrane, R.W., Ménard, D., Yelon, A., (2008) J. Nanos. Nanotechnol., 8 (6), pp. 2944-2954. , 10.1166/jnn.2008.159 1533-4880Joblove, G.H., Greenberg, D., (1978) Computer Graphics (SIGGRAPH '78 Proc. 5th Annual Conference on Computer Graphics and Interactive Techniques), p. 20Aharoni, A., (1998) J. Appl. Phys., 83 (6), p. 3432. , 10.1063/1.367113 0021-8979Hu, C.-L., Magaraggia, R., Yuan, H.-Y., Chang, C.S., Kostylev, M., Tripathy, D., Adeyeye, A.O., Stamps, R.L., (2011) Appl. Phys. Lett., 98 (26). , 10.1063/1.3606556 0003-6951 26250

Buoyancy Organic Rankine Cycle

In the scope of renewable energy, we draw attention to a little known technique to harness solar and geothermal energy. The design here proposed and analyzed is a conceptual hybrid of several patents. By means of a modified organic Rankine cycle, energy is obtained utilizing buoyancy force of a working fluid. Based on thermodynamic properties we propose and compare the performance of Pentane and Dichloromethane as working fluids. Theoretical efficiencies up to 0.26 are estimated for a 51 m (Pentane) and 71.5 m (Dichloromethane) high column of water in a regime below 100°C operation temperature. These findings are especially relevant in the scope of distributed energy systems, combined cycle plants, and low-temperature Rankine cycles. © 2010 Elsevier Ltd.3639991002Şen, Z., Solar energy in progress and future research trends (2004) Progress in Energy and Combustion Science, 30, pp. 367-416Resch, G., Held, A., Faber, T., Panzer, C., Toro, F., Haas, R., Potentials and prospects for renewable energies at global scale (2008) Energy Policy, 36, pp. 4048-4056Poullikaas, A., Implementation of distributed generation technologies in isolated power systems (2007) Renewable and Sustainable Energy Reviews, 11, pp. 30-56Alanne, K., Saari, A., Distributed energy generation and sustainable development (2006) Renewable and Sustainable Energy Reviews, 10, pp. 539-558Shaw, J.B., (1977), Open cycle solar energy system utilizing buoyancy as a conversion force. US patent 4028893Brassea, A., (1997) Buoyancy and thermal differentials energy generator, , US patent 5685147Fries, J.E., (1980), Vapor buoyancy engine. US patent 4196590Schur, G.O., (1975), Thermally powered generating system employing a heat vapor bubble engine. US patent 3916626Scharfengerg, D.S., (2004), Turbine power plant utilizing buoyant force. US patent 6769253 B1Saleh, B., Koglbauer, G., Wendland, M., Fischer, J., Working fluids for low-temperature organic Rankine cycles (2007) Energy, 32, pp. 1210-1221Hettiarachchi, H.D.M., Golubovic, M., Worek, W.M., Ikegami, Y., Optimum design criteria for an organic Rankine cycle using low-temperature geothermal heat sources (2007) Energy, 32, pp. 1698-1706Tu, C.-H., Liu, C.-L., Group-contribution estimation of the enthalpy of vaporization of organic compounds (1996) Fluid Phase Equilibria, 121, pp. 45-65. , http://www.nist.gov/srd, Dichloromethane:, Pentane: NIST database atHung, T.C., Shai, T.Y., Wang, S.K., A review of organic Rankine cycles (ORCs) for the recovery of low-grade waste heat (1997) Energy, 22 (7), pp. 661-667Goswami, D.Y., Vijayaraghavan, S., Lu, S., Tamm, G., New and emerging developments in solar energy (2004) Solar Energy, 76, pp. 33-43Kalogirou, S.A., Solar thermal collectors and applications (2004) Progress in Energy and Combustion Science, 30, pp. 231-29

Recent Experiments And Models On Giant Magnetoimpedance

An overview of the giant magnetoimpedance phenomenon is given in this work. The effect, that consists of drastic changes of the complex impedance of soft magnetic materials upon the application of an external magnetic field, has attracted attention owing to the increasing perspectives of applications on magnetic and stress sensor technology. In particular, asymmetric response is specially indicated for specific applications, and many experimental and theoretical results have been developed so far. A novel approach to investigate the GMI, based on the Fourier analysis of the time derivative of magnetization, will be discussed in further detail. © 2002 Elsevier Science B.V. All rights reserved.3201-4127134Harrison, E.P., Turney, G.L., Rowe, H., Gollop, H., (1937) Proc. R. Soc., 157, p. 651Beach, R.S., Berkowitz, A.E., (1994) J. Appl. Phys., 76, p. 6209Machado, F.L.A., Martins, C.S., Rezende, S.M., (1995) Phys. Rev. B, 51, p. 3926Panina, L.V., Mohri, K., Bushida, K., Noda, M., (1994) J. Appl. Phys., 76, p. 6198Atkinson, D., Squire, P.T., (1997) IEEE Trans. Magn., 33, p. 3364Atkinson, D., Squire, P.T., (1998) J. Appl. Phys., 83, p. 6569Machado, F.L.A., Rezende, S.M., (1996) J. Appl. Phys., 79, p. 6558Panina, L.V., Mohri, K., Ushiyama, T., Noda, M., Bushida, K., (1995) IEEE Trans. Magn., 31, p. 1249Usov, N., (1998) J. Magn. Magn. Mater., 185, p. 159Yelon, A., Menard, D., Britel, M., Ciureanu, P., (1996) Appl. Phys. Lett., 69, p. 3084Makhnovskiy, D.P., Panina, L.V., Mapps, D.J., (2001) Phys. Rev. B, 63, p. 144424Sommer, R.L., Chien, C.L., (1995) Appl. Phys. Lett., 67, p. 3346Beach, R.S., Berkowitz, A.E., (1994) Appl. Phys. Lett., 64, p. 3652Knobel, M., Vázquez, M., Sánchez, M.L., Hernando, A., (1997) J. Magn. Magn. Mater., 169, p. 89Panina, L.V., Mohri, K., (1994) Appl. Phys. Lett., 65, p. 1189Nie, H.B., Pakhomov, A.B., Yan, X., Zhang, X.X., Knobel, M., (1999) Solid State Commun., 112, p. 285Mendes, K.C., Machado, F.L.A., Pereira, L.G., Rezende, S.M., Montenegro, F.C., Altoé, M.V.P., Missell, F.P., (1996) J. Appl. Phys., 79, p. 6555Xiao, S.Q., Liu, Y.H., Dai, Y.Y., Zhang, L., Zhou, S.X., Liu, G.D., (1999) J. Appl. Phys., 85, p. 4127Zhou, Y., Yu, J., Zhao, X., Cai, B., (2000) IEEE Trans. Magn., 36, p. 2960Kraus, L., Knobel, M., Kane, S.N., Chiriac, H., (1999) J. Appl. Phys., 85, p. 5425Pirota, K.R., Kraus, L., Chiriac, H., Knobel, M., (2000) J. Magn. Magn. Mater., 221, pp. L243Guo, H.Q., Kronmuller, H., Dragon, T., Cheng, Z.H., Shen, B.G., (2001) J. Appl. Phys., 89, p. 514Knobel, M., Sánchez, M.L., Gómez-Polo, C., Hernando, A., Marín, P., Vázquez, M., (1995) J. Appl. Phys., 79, p. 1646Knobel, M., Shoenmaker, J., Sinnecker, J.P., Sato Turtelli, R., Grössinger, R., Hofstetter, W., Sassik, H., (1997) Mater. Sci. Eng. A, 226-228, p. 546Mohri, K., Uchiyama, T., Shen, L.P., Cai, C.M., Panina, L.V., (2001) Sens. Act. A, A91, p. 85Knobel, M., GómezPolo, C., Vazquez, M., (1996) J. Magn. Magn. Mater., 160, p. 243Valenzuela, R., Knobel, M., Vazquez, M., Hernando, A., (1995) J. Appl. Phys., 78, p. 5189Kitoh, T., Mohri, K., Ushiyama, T., (1995) IEEE Trans. Magn., 31, p. 3137Panina, L.V., Mohri, K., Makhnovskiy, D.P., (1999) J. Appl. Phys., 85, p. 5444Makhnovskiy, D.P., Panina, L.V., Mapps, D.J., (2000) Appl. Phys. Lett., 77, p. 121Gómez-Polo, C., Vazquez, M., Knobel, M., (2001) Appl. Phys. Lett., 78, p. 246Machado, F.L.A., Rodrigues, A.R., Puça, A.A., De Araújo, A.E.P., (1999) Mater. Sci. Forum, 302-303, p. 202Song, S.-H., Kim, K.-S., Yu, S.-C., Kim, C.G., Vázquez, M., (2000) J. Magn. Magn. Mater., 215-216, p. 532Kim, C.G., Jang, K.J., Kim, H.C., Yoon, S.S., (1999) J. Appl. Phys., 85, p. 5447Song, S.H., Yu, S.-C., Kim, C.G., Kim, H.C., Lim, W.Y., (2000) J. Appl. Phys., 87, p. 5266Blanco, J.M., Zhukov, A., Chen, A.P., Cobeno, A.F., Chizhik, A., Gonzalez, J., (2001) J. Phys. D: Appl. Phys., 34, pp. L31-L34Chen, D.-X., Pascual, L., Hernando, A., (2000) Appl. Phys. Lett., 77, p. 1727Kim, C.G., Jang, K.J., Kim, D.Y., Yoon, S.S., (1999) Appl. Phys. Lett., 75, p. 2114Kim, C.G., Jang, K.J., Kim, D.Y., Yoon, S.S., (2000) Appl. Phys. Lett., 77, p. 1730Gómez-Polo, C., Vazquez, M., Pirota, K.R., Knobel, M., (2001) Physica B, 299, p. 322Landau, L., Lifshitz, E.M., (1975) Electrodynamics of Continuous Media, , Pergamon, New YorkPirota, K.R., Sartorelli, M.L., Knobel, M., Shoenmaker, J., Gutierrez, J., Barandiarán, J.M., (1999) J. Magn. Magn. Mater., 202, p. 431Borhöfft, W., Trenkler, G., (1989) Sensors: A comprehensive survay, , VHC, New YorkPirota, K.R., Kraus, L., Knobel, M., Pagliuso, P.G., Rettori, C., (1999) Phys. Rev. B, 60, p. 668

One Step Chemical Synthesis Of Ag-fe3o4 Heterodimer Nanoparticles: Optical, Structure, And Magnetic Properties

Optical, magnetic and structural properties of one-step chemical decomposition approach Ag-Fe3O4 heterodimer structures are reported. We synthesized Ag-Fe3O4 nanoparticles where the Ag nanoparticles of less than 10 nm are physically attached to Fe 3O4 nanoparticles also less than 10 nm. The structural properties of the samples were characterized from X-ray diffraction (XRD) and transmission electron microscopy (TEM) data, which confirmed the existence of heterodimer structures in solution along with isolated magnetite nanoparticles. Optical properties of the obtained samples were studied using UV/vis spectra and compared with Fe3O4 reference nanoparticles in absence of metallic component. Magnetization hysteresis loops for the obtained samples along with Fe3O4 reference sample at 2 K (blocked regime), 50 K (intermediate regime) and 300 K (superparamagnetic regime) and with maximum applied field of ± 20 kOe were performed and correlated to the structural data. Also, magnetization versus temperature curves (Field Cooling-Zero Field Cooling) with static magnetic field of 50 Oe were measured, from which the blocking temperature of the heterodimer sample was about 77 K and for the reference less than 20 K. © 1965-2012 IEEE.49846064609Jain, P.K., El Sayed, I.H., El Sayed, M.A., Au nanoparticles target cancer (2007) Nanotoday, V21, p. 18Arruebo, M., Ferńndez-Pacheco, R., Ibarra, M.R., Santamaría, J., Magnetic nanoparticles for drug delivery (2007) Nanotoday, 2 (3), p. 22Pankhurst, Q.A., Connolly, J., Jones, S.K., Dobson, J., Applications of magnetic nanoparticles in biomedicine (2003) J. Phys. D: App. Phys., 36, pp. R167Lee, H., Jang, J.T., Choi, J.S., Moon, S.H., Noh, S.H., Kim, J.W., Kim, J.G., Cheon, J., Exchange-coupled magnetic nanoparticles for efficient heat induction (2011) Nat. Nanot., 6, p. 418Wang, C., Yin, H.F., Dai, S., Sun, S., A general approach to noble Metal-Oxide dumbbell nanoparticles and their catalytic application for CO oxidation (2010) Chem. Mater., 22, p. 3277Lopes, G., Vargas, J.M., Sharma, S.K., Béron, F., Pirota, K.R., Knobel, M., Rettori, C., Zysler, R.D.J., Ag-Fe O dimer colloidal nanoparticles: Synthesis and enhancement of magnetic properties (2010) Phys. Chem., C114, p. 10148Muraca, D., Sharma, S.K., Socolovsky, L.M., De Siervo, A., Lopes, G., Pirota, K.R., Influence of silver concentrations on structural and magnetic properties of Ag-Fe O heterodimer nanoparticles (2012) J. Nanosci. Nanotech., 12, p. 6961Huang, J., Sun, Y., Huang, S., Yu, K., Zhao, Q., Peng, F., Yu, H., Yang, J., (2011) J. Mater. Chem, 21, p. 17930Jones, M.R., Osberg, K.D., Macfarlane, R.J., Langille, M.R., Mirkin, C.A., Templated techniques for the synthesis and assembly of plasmonic nanostructures (2011) Chem. Rev., 111, p. 3736Lin, X.Z., Teng, X., Yang, H., Direct synthesis of narrowly dispersed silver nanoparticles using a single-source precursor (2003) Langmuir, 19, p. 10081Mayer, K.M., Hafner, J.H., Localized surface plasmon resonance sensors (2011) Chem. Rev., 111, p. 3828Lermé, J., Size evolution of the surface plasmon resonance damping in silver nanoparticles: Confinement and dielectric effects (2011) J. Phys. Chem. C, 115, p. 14098Wiley, B.J., Sang, H.I., Zhi-Yuan, L., McLellan, J., Siekkinen, A., Younan, X., Maneuvering the surface plasmon resonance of silver nanostructures through shape-controlled synthesis (2006) J. Phys. Chem. B., 110, p. 15666Goya, G.F., Berquó, T.S., Fonseca, F.C., Morales, M.P., Static and dynamic magnetic properties of spherical magnetite nanoparticles (2003) J. Appl. Phys., 94 (3520)Morales, M.P., Veintemillas-Verdaguer, S., Montero, M.I., Serna, C.J., Surface and internal spin canting in -Fe O nanoparticles (1999) Chem. Mater., 11, p. 3058Muraca, D., De Siervo, A., Pirota, K.R., From quenched to unquenched orbital magnetic moment on metallic-oxide nanoparticles: DC magnetic properties and electronic correlation (2013) J. Nanopart. Res., 15, p. 137