Spin-polarized plasmon in ferromagnetic metals

We have summarized some important results of the anisotropic transport properties of the prototypical manganite La 1-x Ca x MnO 3 as well as a few others. The temperature dependence of anisotropic magnetoresistance in manganites exhibits a peak near the magnetic ordering temperature which differs dramatically from the ones in 3d ferromagnetic metals and alloys. Depending on the strain-driven orbital state, the AMR in manganites could be enhanced dramatically. The AMR in manganites is much larger than in ferromagnetic metals, where its magnitude is only of the order of a few percent. At low fields (below few kG) the intrinsic magnetocrystalline anisotropy becomes important and the dependence of resistance on angle changes to a more switching-like behavior. The magnitude of the switching is sufficiently large such that this phenomenon could be useful in spintronics for magnetic field sensing and nonvolatile memory applications. Moreover, at temperatures far below the metal insulator transition temperatures, the AMR in LCMO/LAO also flips and changes a sign in contrast to LCMO/STO films. Also sign flip takes place in charge and orbital ordered manganites exhibiting field induced ferromagnetism. Polycrystalline manganite samples also exhibit strong AMR. At lower temperatures the dependence of the AMR on temperature is dramatically different in polycrystalline samples than the epitaxial or single crystal samples. The behavior in the the polycrystalline samples could be governed by spin-polarized transport across the grain boundaries.

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Spin polarized positron lifetimes in ferromagnetic metals: First-principles study

Japanese Journal of Applied Physics ◽

10.7567/jjap.53.053002 ◽

2014 ◽

Vol 53 (5) ◽

pp. 053002 ◽

Cited By ~ 7

Author(s):

Jianbo Lin ◽

Takahiro Yamasaki ◽

Mineo Saito

Keyword(s):

First Principles ◽

Ferromagnetic Metals ◽

First Principles Study ◽

Spin Polarized ◽

Positron Lifetimes

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Calculation of the magneto-optical properties of ferromagnetic metals using the spin-polarized relativistic LMTO method

Journal of Magnetism and Magnetic Materials ◽

10.1016/0304-8853(95)01083-1 ◽

1995 ◽

Vol 146 (1-2) ◽

pp. 205-207 ◽

Cited By ~ 61

Author(s):

V.N Antonov ◽

A.Ya Perlov ◽

A.P Shpak ◽

A.N Yaresko

Keyword(s):

Optical Properties ◽

Ferromagnetic Metals ◽

Spin Polarized ◽

Lmto Method

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Fundamental Limitations of Half-Metallicity in Spintronic Materials

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.215.22 ◽

2014 ◽

Vol 215 ◽

pp. 22-27 ◽

Cited By ~ 1

Author(s):

Alexander Solontsov

Keyword(s):

Ground State ◽

Low Frequency ◽

Zero Point ◽

Spin Fluctuations ◽

Half Metallicity ◽

Half Metallic ◽

Strong Damping ◽

Ferromagnetic Metals ◽

Fundamental Limitations ◽

Spin Polarized

Zero-point spin fluctuations are shown to strongly influence the ground state of ferromagnetic metals and to impose limitations for the fully spin polarized state assumed in half-metallic ferromagnets, which may influence their applications in spintronics. This phenomenon leads to the low-frequency Stoner excitations and cause strong damping and softening of magnons in magnetoresistive manganites observed experimentally.

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A simple model for the interpretation of spin-polarized photoemission spectra of ferromagnetic metals

Journal of Magnetism and Magnetic Materials ◽

10.1016/0304-8853(92)90977-v ◽

1992 ◽

Vol 104-107 ◽

pp. 671-672 ◽

Cited By ~ 1

Author(s):

Alfred Ziegler

Keyword(s):

Simple Model ◽

Ferromagnetic Metals ◽

Spin Polarized

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New Materials for Spintronics

MRS Bulletin ◽

10.1557/mrs2003.210 ◽

2003 ◽

Vol 28 (10) ◽

pp. 706-710 ◽

Cited By ~ 65

Author(s):

Scott A. Chambers ◽

Young K. Yoo

Keyword(s):

Magnetic Semiconductors ◽

Spin Injection ◽

Heusler Alloys ◽

Host Lattice ◽

New Materials ◽

New Class ◽

Ferromagnetic Metals ◽

Current State ◽

Spin Polarized ◽

Injection Materials

AbstractThis article introduces the October 2003 issue of MRS Bulletin on “New Materials for Spintronics.” As a result of quantum mechanics, the carriers in ferromagnetic metals such as Fe, Co, and Ni are spin-polarized due to an imbalance at the Fermi level in the number of spin-up and spin-down electrons. A carrier maintains its spin polarization as long as it does not encounter a magnetic impurity or interact with the host lattice by means of spin-orbit coupling. The discovery of optically induced, long-lived quantum coherent spin states in semiconductors has created a range of possibilities for a new class of devices that utilize spin. This discovery also points to the need for a wider range of spin-polarized materials that will be required for different device configurations. In this issue of MRS Bulletin, we focus on three classes of candidate spintronic materials and review the current state of our understanding of them: III–V and II–VI semiconductors, oxides, and Heusler alloys. The field of spin-polarized materials is growing very rapidly, and the search for new magnetic semiconductors and other suitable spin-injection materials with higher Curie temperatures is bringing spintronics closer to the realm of being practical.

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Studies of ferromagnetic metals by electron spin polarized tunneling

Journal of Applied Physics ◽

10.1063/1.327117 ◽

1979 ◽

Vol 50 (B3) ◽

pp. 1935-1939 ◽

Cited By ~ 7

Author(s):

R. Meservey ◽

P. M. Tedrow ◽

V. R. Kalvey ◽

D. Paraskevopoulos

Keyword(s):

Electron Spin ◽

Ferromagnetic Metals ◽

Spin Polarized ◽

Spin Polarized Tunneling

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Spin-polarized Scanning Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100176976 ◽

1990 ◽

Vol 48 (4) ◽

pp. 768-769

Author(s):

Kazuyuki Koike ◽

Hideo Matsuyama

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

High Speed ◽

Magnetic Thin Films ◽

Electron Spin Polarization ◽

Acquisition Time ◽

Magnetization Direction ◽

Spin Polarized ◽

Conventional Methods ◽

Scanning Electron

Spin-polarized scanning electron microscopy (spin SEM), where the secondary electron spin polarization is used as the image signal, is a novel technique for magnetic domain observation. Since its first development by Koike and Hayakawa in 1984, several laboratories have extensively studied this technique and have greatly improved its capability for data extraction and its range of applications. This paper reviews the progress over the last few years.Almost all the high expectations initially held for spin SEM have been realized. A spatial resolution of several hundreds angstroms has been attained, which is nearly one order of magnitude higher than that of conventional methods for thick samples. Quantitative analysis of magnetization direction has been performed more easily than with conventional methods. Domain observation of the surface of three-dimensional samples has been confirmed to be possible. One of the drawbacks, a long image acquisition time, has been eased by combining highspeed image-signal processing with high speed scanning, although at the cost of image quality. By using spin SEM, the magnetic structure of a 180 degrees surface Neel wall, magnetic thin films, multilayered films, magnetic discs, etc., have been investigated.

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