Quantum Well States in Fe/Nb(001) Multilayers: First Principles Study
Abstract
A first principle study to understand the phenomena of interlayer exchange coupling in Fe/Nb multilayers using the linearized-muffin-tin-orbitals method within the generalized gradient approximation was performed. It was observed that the exchange coupling oscillates with both short and long periodicals, which have been examined in terms of Ruderman-Kittel-Kasuya-Yosida (RKKY) model as well as the Quantum well (QW) model. The behavior of the exchange coupling was investigated by artificially varying moments of Fe atoms in ferromagnetic layers. For small moments of Fe, the coupling shows bilinearity in the magnetic moments implying its RKKY character. However, at higher moments close to the bulk F, the saturation of long-period oscillations is in accordance with the QW model. Quantum well dispersions around the Fermi level demonstrate that the majority-spin bands contribute largely to the formation of quantum-well states, which was analyzed quantitatively by making use of the phase accumulation model. The analysis indicates that the quantum well model gives a better description of the oscillatory behavior of the exchange coupling in Fe/Nb multilayers.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 06, 2007
- Accession Number
- ADA474832
Entities
People
- A. Sen
- Nitya N. Sliukia
- R. Prasad
Organizations
- Indian Institute of Technology Kanpur