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Your search keyword '"Vaurès A"' showing total 3 results
Start Over Author "Vaurès A" Topic physics
3 results on '"Vaurès A"'

1. Inverse Tunnel Magnetoresistance inCo/SrTiO3/La0.7Sr0.3MnO3: New Ideas on Spin-Polarized Tunneling

Author

François Montaigne, Agnès Barthélémy, R. Lyonnet, Albert Fert, A. Vaurès, Pierre Seneor, J.-P. Contour, and J. M. De Teresa

Subjects
Physics, Condensed matter physics, Spin polarization, Spin polarized tunneling, General Physics and Astronomy, Inverse, Electron, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, Condensed Matter::Materials Science, Tunnel magnetoresistance, Density of states, Condensed Matter::Strongly Correlated Electrons, Quantum tunnelling, Spin-½
Abstract

We report tunnel magnetoresistance (TMR) measurements on $\mathrm{Co}/{\mathrm{SrTiO}}_{3}/{\mathrm{La}}_{0.7}{\mathrm{Sr}}_{0.3}{\mathrm{MnO}}_{3}$ junctions. The half-metallic ${\mathrm{La}}_{0.7}{\mathrm{Sr}}_{0.3}{\mathrm{MnO}}_{3}$ electrode is used as a spin analyzer. The large $(\ensuremath{-}50%)$ inverse TMR indicates a negative spin polarization of Co, in agreement with the density of states (DOS) of the $d$ band in Co. The bias dependence of the TMR, with a maximum inverse TMR at $\ensuremath{-}0.4\mathrm{V}$ and a crossover to normal TMR above $+0.8\mathrm{V}$, reflects the structure of this DOS. Our results demonstrate that the choice of the insulating barrier can strongly influence and even reverse the spin polarization of tunneling electrons.

Published
1999
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2. Spin-transfer-induced domain wall motion in a spin valve.

Author

Grollier, J., Boulenc, P., Cros, V., Hamzic, A., Vaurès, A., Fert, A., and Faini, G.

Subjects
MAGNETIC fields, SPIN valves, MOTION, POLARIZATION (Nuclear physics), NANOWIRES, PHYSICS
Abstract

We have studied the current-induced displacement of a domain wall (DW) in the permalloy (Py) layer of a Co/Cu/Py spin-valve structure. At zero and very small applied fields (<10 Oe), the displacement is in opposite direction for opposite dc currents, and the current density required to move DW is of the order of a few 106 A/cm2. At higher applied magnetic fields, the DW motion, even though triggered by the current, has its direction controlled by the field. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Published
2004
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3. Sharp assembly of small clusters obtained by atom deposition for room temperature Coulomb blockade.

Author

Lidgi-Guigui, N., Seneor, P., Nguyen Van Dau, F., Friederich, A., Vaurès, A., and Deranlot, C.

Subjects
CLUSTER theory (Nuclear physics), ATOMS, PLASMA gases, COULOMB functions, PHYSICS experiments, PHYSICS
Abstract

The growth of a nanocluster assembly on a processed AlOx and its electronic transport behavior are investigated. An Ar+ plasma was used in order to create defects of high trapping energy on an AlOx layer. This process promotes a shift of the cluster distribution towards smaller sizes and allows to sharpen it. In a second part, the authors show that the application of this techniqueto clusters inserted in a tunnel junction can lead to a dramatic increase in the temperature range over which Coulomb blockade can be observed. [ABSTRACT FROM AUTHOR]

Published
2007
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