Browsing by Author "COEY, JOHN"
Now showing items 1-20 of 92
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Biaxial strain-induced transport property changes in atomically tailored SrTiO3 -based systems
(2014)Several metallic SrTiO3-based systems, including reduced SrTiO3−δ, Nb-doped SrTiO3, and two-dimensional electron gas at the LaAlO3/SrTiO3(001) interface, have been epitaxially fabricated on various substrates inducing ... -
Boron diffusion in magnetic tunnel junctions with MgO (001) barriers and CoFeB electrodes
(2010)Boron diffusion out of the CoFeB layers in model systems with thick CoFeB and MgO layers grown by radiofrequency sputtering or electron-beam evaporation and in MgO-based magnetic tunnel junctions (MTJs) is probed after ... -
Charge freezing and surface anisotropy on magnetite (100)
(1993)Scanning tunneling microscope images of the (100) surface of slightly nonstoichiometric magnetite taken at room temperature show static arrays of pairs of Fe2+ ions with short?range order, and a charge fluctuation time ... -
Conductance enhancement due to interface magnons in electron-beam evaporated MgO magnetic tunnel junctions with CoFeB free layer deposited at different pressure
(2014)Electron-beam evaporated MgO-based magnetic tunnel junctions have been fabricated with the CoFeB free layer deposited at Ar pressure from 1 to 4 mTorr, and their tunneling process has been studied as a function of ... -
Conducting channel at the LaAlO3/SrTiO3 interface
(2013)Localization of electrons in the two-dimensional electron gas at the LaAlO3/SrTiO3 interface is investigated by varying the channel thickness in order to establish the nature of the conducting channel. Layers of SrTiO3 ... -
Conventional and inverse magnetocaloric effects in La(0.45)Sr(0.55)MnO(3) nanoparticles
(2011)The magnetocaloric effect of La(0.45)Sr(0.55)MnO(3) nanoparticles was studied by dc magnetization measurements. A sample with mean particle size of about 140 nm exhibits both a conventional magnetocaloric effect around the ... -
Cooling-field dependence of exchange bias effect in La 0.45Sr0.55MnO3 nanoparticles
(2014)Magnetic properties of 16 nm La0.45Sr0.55MnO3 nanoparticles exhibit superparamagnetic blocking at 160 K with a ferromagnetic moment appearing in the antiferromagnetic state. The exchange interaction at the interface between ... -
CoTaZr/Pd multilayer with perpendicular magnetic anisotropy
(AIP Publishing, 2013)We report a novel perpendicularly magnetized thin film [Co91.5 Ta 4.5Zr4/Pd]5 multilayer, which exhibits strong perpendicular magnetic anisotropy when grown on 5 nm of Pd and Ru seed layers. The Pd-seeded multilayer annealed ... -
Cubic Mn 2 Ga Thin films: Crossing the spin gap with ruthenium
(2014)Cubic Mn2Ga films with the half-Heusler C1b structure are grown on V (001) epitaxial films. The phase is a soft ferrimagnet, with Curie temperature TC = 225 K and magnetization Ms=280 kA m−1, equivalent to 1.65μB per ... -
Dependence of charge carrier injection on the interface energy barrier in short-channel polymeric field effect transistors
(2012)The influence of contact materials on the electrical characteristics of field-effect transistors made from poly(3-hexylthiophene) with short-channel lengths of 80nm is investigated. The thermally activated output current ... -
Designing a fully compensated half-metallic ferrimagnet
(2016)Recent experimental work on Mn 2 Ru x Ga demonstrates its potential as a compensated ferrimagnetic half metal (CFHM). Here we present a set of high-throughput ab initio density functional theory calculations and a ... -
Diameter-modulated ferromagnetic CoFe nanowires
(2013)Highly ordered nanoporous anodic aluminium oxide templates with uniform or periodically modulated pore diameters have been fabricated by the hard-pulse anodization technique. Straight and diameter-modulated CoFe nanowires ... -
Dynamic response of ammonia sensors constructed from polyaniline nanofibre films with varying morphology
(2012)Polyaniline is acid-doped with HCl, HNO3, HClO4, HBr or H2SO4 to yield thin films that are nanofibrous or dense. The nanofibrous films show a faster response to ammonia gas, and the response is greater when the films are ... -
Electrodeposition of coercive L10 FePd and FePt magnets
(Elsevier, 2010)We report the preparation, characterization of structure and magnetic properties of electrodeposited L10 FePt films with high coercivity. Equiatomic as-deposited films are nanocrystalline, soft and magnetically isotropic. ... -
Electron and spin transport studies of gated lateral organic devices
(2012)In view of the many, often contradictory, reports of magneto-resistance (M R) in spin valve stacks containing a layer of organic semiconductor, mostly of the small molecule variety, we have investigated interdigitated ... -
Enhanced energy product in Y-Co-Fe magnets intermediate between Nd-Fe-B and ferrite
(2015)The hysteresis of ball-milled Fe-doped YCo5 powder has been optimized by controlling the temperature and time for rapid annealing under vacuum and argon. The crystallite size is only 25 nm; yet, it has been possible to ... -
Exchange-biased magnetic tunnel junctions with antiferromagnetic epsilon-Mn3Ga
(2012)Oriented c-axis films of the hexagonal triangular antiferromagnetic ?-Mn3Ga have been used in bottom-pinned synthetic antiferromagnetmagnetic tunnel junctions with MgO barriers, which show up to 150% tunneling magnetoresistance ... -
Fermi level spin polarization of polycrystalline thulium by point contact Andreev reflection spectroscopy
(2011)The spin polarization near the Fermi level in bulk polycrystalline ferrimagnetic thulium is investigated by means of point contact Andreev reflection (PCAR), in the temperature interval (1.9?9.2 K). The highest polarization ...
