Magnetic nanowires

Keywords Spark Plasma Sintering under magnetic field magnetic nanowires magnetic coercivity nanostructured magnets with tunable properties. 

Semiconductor Magnetic nanowires Magnetic nanowire Fasol and Runge... 

Felton EJ, Reich DH (2007) Biological applications of multifunctional magnetic nanowires. In Labhasetwa V, Leslie-Pelecky DL (eds) Biomedical applications of nanotechnology. Wiley, Hoboken, pp 1-22 doi 10.1002/9780470152928 chi... 

There is considerable interest in developing new types of magnetic materials, with a particular hope that ferroelectric solids and polymers can be constructed— materials having spontaneous electric polarization that can be reversed by an electric field. Such materials could lead to new low-cost memory devices for computers. The fine control of dispersed magnetic nanostructures will take the storage and tunability of magnetic media to new levels, and novel tunneling microscopy approaches allow measurement of microscopic hysteresis effects in iron nanowires. 

A. K. Bentley, J. S. Trethewey, A. B. Ellis, and W. C. Crone, Magnetic manipulation of copper-tin nanowires capped with nickel ends. Nano Lett. 4(3), 487-490 (2004). 

Figure 1.34 Experimental setup showingthe nickel nanowires in a (A) horizontal and (B) vertical position depending on the magnetic field orientation. (Reprinted with permission from Ref. [171]. 2006 American Chemical Society.)...

Rgure 2.16. Long magnetic nanowires made by submitting a mixture of magnetic particles and PAA to a magnetic field. The chains are bent by gravity after field removal. (Reproduced with permission from [47].)... 

C. Goubault, E. Leal-Calderon, J.-L. Viovy, and J. Bibette Self-Assembled Magnetic Nanowires Made Irreversible by Polymer Bridging. Langmuir 21, 3725 (2005). 

This chapter deals with the selective preparation, TEM/EXAFS/XPS characterization and catalysis of mono- and bimetallic nanowires and nanoparticles highly ordered in silica FSM-16, organosilica HMM-1 and mesoporous silica thin films. The mechanism of nanowire formation is discussed with the specific surface-mediated reactions of metal precursors in the restraint of nanoscale void space of mesoporous silica templates. The unique catalytic performances of nanowires and particles occluded in mesoporous cavities are also reviewed in terms of their shape and size dependency in catalysis as well as their unique electronic and magnetic properties for the device application. 

Figure 9 Left Schematic representation of chemical or UV-induced synthesis of Pt nanowires and nanoparticles in zeolites FSM-16. Right Comparison of temperature dependence of magnetization for Pt nanowires and nanoparticles in FSM-16. (From Ref. 137.)...

Finally, magnetic nanowires and other submicrometer-scale anisometric particles can also be manipulated and organized via controlled spatial variations in the alignment of nematic liquid crystals. Leheny and co-workers, for example, measured the elastic forces imposed on anisotropic Ni nanowires suspended in a nematic liquid crystal (here 5CB, Fig. 13a), and showed that by applying a magnetic field the nanowire reorients and distorts the director in the adjacent area [445, 446]. 

Fig. 13 Schematic representation of the orientation-dependent elastic torque on a nickel nanowire with longitudinal anchoring in 5CB (a) in equilibrium, and (b) in the presence of a magnetic field, (c) Levitation of the nanowire in a twisted nematic cell [446]. (Copyright 2004, American Association for the Advancement of Science)...

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