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Your search keyword '"SPIN polarization"' showing total 3 results
3 results on '"SPIN polarization"'

1. Spin current in an electron waveguide tunnel-coupled to topological insulator

Author

Vladimir A. Sablikov and Aleksei A. Sukhanov

Subjects
Physics, Condensed Matter - Mesoscale and Nanoscale Physics, Condensed matter physics, Spin polarization, Electric Conductivity, FOS: Physical sciences, Electron, Condensed Matter Physics, Polarization (waves), Electron Transport, Models, Chemical, Electrical resistivity and conductivity, Luttinger liquid, Topological insulator, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Computer Simulation, Spin Labels, General Materials Science, Electron scattering, Quantum tunnelling
Abstract

We show that electron tunneling from edge states in two-dimensional topological insulator into a parallel electron waveguide leads to the appearance of spin-polarized current in the waveguide. The spin polarization $P$ can be very close to unity and the electron current passing through the tunnel contact splits in the waveguide into two branches flowing from the contact. The polarization essentially depends on the electron scattering by the contact and the electron-electron interaction in the one-dimensional edge states. The electron-electron interaction is treated within the Luttinger liquid model. The main effect of the interaction stems from the renormalization of the electron velocity, due to which the polarization increases with the interaction strength. Electron scattering by the contact leads to a decrease in $P$. A specific effect occurs when the bottom of the subbands in the waveguide crosses the Dirac point of the spectrum of edge states when changing the voltage or chemical potential. This leads to changing the direction of the spin current., Comment: 11 pages, 5 figures, accepted in J. Phys.: Condens. Matter

Published
2012
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2. Electronic, Magnetic, and Structural Properties of Sr2MnRuO6 and LaSrMnRuO6 Double Perovskites.

Author

Woodward, Patrick M., Goldberger, Joshua, Stoltzfus, Matthew W., Eng, Hank W., Ricciardo, Rebecca A., Santhosh, Padmam N., Karen, Pavel, and Moodenbaugh, Arnold R.

Subjects
MAGNETIC properties, PEROVSKITE, STRONTIUM compounds, MANGANESE compounds, LANTHANUM compounds, NEUTRON diffraction, PHASE transitions, ELECTRIC conductivity, PHYSICS
Abstract

The perovskites Sr2MnRuO6 and LaSrMnRuO6 have been investigated and their properties compared with those of the broader family of A2MRuO6 double perovskites (A=Sr, La; M=Cr, Mn, Fe, Co, Ni). Neutron powder diffraction shows that both phases lack long-range Mn/Ru order. Sr2MnRuO6 exhibits a cooperative Jahn–Teller distortion, conductivity that proceeds via variable-range hopping, and antiferromagnetic (AFM) order (C-type structure, TN≅200K, 2.05(1) μB per transition metal). LaSrMnRuO6 exhibits nearly undistorted octahedra, conductivity that proceeds via diffusion-assisted small-polaron hopping, and ferromagnetic (FM) order ( TC≅220K, 1.60(4) μB transition metal). Band structure calculations show that AFM Mn–O–Ru coupling optimizes polarization of the Ru t2 g orbitals, while FM coupling favors delocalization of the Ru t2 g electrons. The transition from antiferromagnetism to ferromagnetism is linked to a loss of orbital order and stabilized over competing glassy states by delocalization of Ru t2 g electrons. [ABSTRACT FROM AUTHOR]

Published
2008
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3. Temperature Dependence of Spin Transfer Switching in Nanosecond Regime.

Author

Apalkov, Dmytro, Zhitao Diao, Panchula, Alex, Shengyuan Wang, Yiming Huai, and Kawabata, Kiyoshi

Subjects
ELECTRIC conductivity, QUANTUM tunneling, THERMAL properties, THIN films, SPINTRONICS, NANOTECHNOLOGY, PHYSICS
Abstract

We present a micromagnetic modeling study of spin transfer (ST) switching in magnetic tunneling junctions (MTJs) and its dependence on thermal effects due to a finite temperature of the MTJ. It is shown that the major effect of temperature is the introduction of nonzero distribution of local magnetization deviation from the easy axis of the free layer. The study of asymmetry between antiparallel (AP) to parallel (P) and P to AP switching is presented. [ABSTRACT FROM AUTHOR]

Published
2006
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