Quantum-Well Contributions to the RKKY Coupling in Magnetic Multilayers

1993 ◽  
Vol 313 ◽  
Author(s):  
B. A. Jones ◽  
C. B. Hanna
Keyword(s):  
Quantum Well ◽  
Fermi Surface ◽  
Free Electron ◽  
Bound States ◽  
Finite Size ◽  
Oscillation Period ◽  
Magnetic Multilayers ◽  
Potential Well ◽  
Experimental Systems ◽  
Quantum Well States

ABSTRACTWe study the effects of quantum-well states on the calculated RKKY coupling. We find that the bound states of a finite-size potential well of depth V give an added oscillation period of size For the simplest case of a spherical free-electron Fermi surface, thus two periods appear: the original, “fast,” π/kf oscillation, and the quantum-well one The quantum-well contributions have larger amplitude, and are in fact the predominant oscillation. For physically reasonable V (tenths of an eV) this period is around 8–10Å. We discuss evidence for these effects in experimental systems.

Interface reflectivities and quantum-well states in magnetic multilayers

1998 ◽  
Vol 58 (20) ◽  
pp. 13721-13733 ◽  
Author(s):  
K. Wildberger ◽  
R. Zeller ◽  
P. H. Dederichs ◽  
J. Kudrnovský ◽  
P. Weinberger
Keyword(s):  
Quantum Well ◽  
Magnetic Multilayers ◽  
Quantum Well States

Quantum-well states and exchange coupling in fcc (111) magnetic multilayers

1994 ◽  
Vol 50 (21) ◽  
pp. 16066-16069 ◽  
Author(s):  
D. M. Edwards ◽  
J. Mathon ◽  
R. B. Muniz
Keyword(s):  
Quantum Well ◽  
Exchange Coupling ◽  
Magnetic Multilayers ◽  
Quantum Well States

Hybridization and the effective mass of quantum-well states in magnetic multilayers

1994 ◽  
Vol 50 (12) ◽  
pp. 8954-8956 ◽  
Author(s):  
P. D. Johnson ◽  
K. Garrison ◽  
Q. Dong ◽  
N. V. Smith ◽  
Dongqi Li ◽  
...  
Keyword(s):  
Quantum Well ◽  
Effective Mass ◽  
Magnetic Multilayers ◽  
Quantum Well States

Quantum well States in Fe (100) Ultrathin Films Observed by Magneto-Optical Effect

1993 ◽  
Vol 313 ◽  
Author(s):  
Yoshishige Suzuki ◽  
Toshikazu Katayama
Keyword(s):  
Quantum Well ◽  
Ultrathin Films ◽  
Oscillation Period ◽  
Interlayer Thickness ◽  
Kerr Rotation ◽  
Magnetic Layers ◽  
Ultrathin Layers ◽  
Spin Polarized ◽  
Magneto Optical Effect ◽  
Quantum Well States

ABSTRACTWe report on the Magneto-optical Kerr rotation (<φ>K) spectra of ultrathin Fe films on Au or Ag (100) substrates and the φK oscillation due to interlayer thickness in Fe/Au/Fe sandwich films. In 3.5–4.5 eV, a new φK peak appears in the bcc-Fe (100) ultrathin films on the fcc-Au (100) surface and it shifts towards the higher energy side with increasing Fe layer thickness. The absolute value of eXy for 3Å (2ML) thick Fe layers is twice as large as that of bulk Fe at 3.7 eV. The thickness dependence of the transition energy of this new peak in the spectra is well explained by the concept of quantum well states in the Fe ultrathin layers, attributing the new transition to a transition from the majority spin Δ5 band ({px±i py), {dxz±i dyZ}; M=±l) to the Δ1 quantum well states (s, pz, dz2; M=0). The new peak is also observed in the Fe/Au (100) artificial superlattices. Using the εxy obtained experimentally for the Fe ultrathin films and the εxy of literature, we can reproduce the experimental φK spectra of the artificial superlattices by optical calculation. On the other hand, we cannot observe the same behavior for the ultrathin Fe films grown on a fcc-Ag (100) surface and covered by a Au (100) ultrathin film, although the εXy of Fe is different from that of the bulk and shows some structures in 2–3 eV. These structures around 2.5 eV are thought to be due to polarized Au atoms adjacent to an Fe layer.An oscillation of φK as a function of interlayer thickness, d, was observed in photon energy region between about 2.5 and 3.8 eV for the Fe (6Å) /Au (dÅ) /Fe (6A) sandwiched film. The oscillation period was about 10Å (5ML) of Au. The oscillation is thought to be closely related with a formation of spin polarized quantum well states of Δ1 band in Au layers sandwiched by magnetic layers.

Influence of Superlattice Potentials on Transport in magnetic multilayers

1993 ◽  
Vol 313 ◽  
Author(s):  
Shufeng Zhang ◽  
Peter M. Levy
Keyword(s):  
Quantum Well ◽  
Magnetic Multilayers ◽  
Multilayered Structures ◽  
Primary Origin ◽  
Spin Dependent Scattering ◽  
Quantum Well States

ABSTRACTWe discuss the effect of the superlattice potential on the magnetotransport properties of magnetic multilayers for current parallel and perpendicular to the plane of the layers. While quantum well states affect the Magnetotransport, they are not the primary origin of the giant Magnetoresistance observed in these materials for currents in the plane of the layers. In general, it is necessary to include both spin-dependent scattering and the effects of superlattice potentials in order to explain the magnetoresistance of multilayered structures.

QUANTUM WELL STATES IN METALLIC THIN LAYERS

1997 ◽  
Vol 04 (02) ◽  
pp. 361-370 ◽  
Author(s):  
J. E. ORTEGA ◽  
F. J. HIMPSEL ◽  
G. J. MANKEY ◽  
R. F. WILLIS
Keyword(s):  
Thin Film ◽  
Quantum Well ◽  
Magnetic Multilayers ◽  
Thin Layers ◽  
Bulk Solid ◽  
Quantum Well State ◽  
Spin Polarized ◽  
Photoemission Data ◽  
Oscillatory Coupling ◽  
Quantum Well States

When going from the bulk solid to a thin film of nanometer dimensions, the electronic structure becomes discretized in the perpendicular direction. These discrete states, also called thin film states and quantum well states, are clearly distinguished in photoemission experiments as two-dimensional and thickness-dependent modulations of the bulk spectra, although their observation is limited to highly perfect epitaxial systems. The photoemission data are well explained in the framework of a simple model for the electron wave function in a quantum well state. Thin film states become spin-polarized when growing on ferromagnetic substrates. Furthermore, spin-polarized, thickness-dependent modulations at a given energy lead to spin-dependent periodic oscillations of the density of states as a function of thickness, which are found to be responsible for the oscillatory coupling observed in magnetic multilayers.

Sign in / Sign up

Export Citation Format

Share Document