skip to main content

Title: Unusual spin correlations in a nanomagnet

We show how atomic-scale exchange phenomena can be controlled and exploited in nanoscale itinerant magnets to substantially improve magnetic properties. Cluster-deposition experiments, first-principle simulations, and analytical calculations are used to demonstrate the effect in Co{sub 2}Si nanoclusters, which have average sizes varying from about 0.6 to 29.5 nm. The cluster-deposited nanoparticles exhibit average magnetic moments of up to 0.70 μ{sub B}/Co at 10 K and 0.49 μ{sub B}/Co at 300 K with appreciable magnetocrystalline anisotropies, in sharp contrast to the nearly vanishing bulk magnetization. The underlying spin correlations and associated cluster-size dependence of the magnetization are explained by a surface induced ferromagnetic spin polarization with a decay length of the order of 1 nm, much larger than the nearest-neighbor interatomic distance in the alloy.
Authors:
; ; ; ; ; ;  [1] ;  [2] ;  [3]
  1. Nebraska Center for Materials and Nanoscience, University of Nebraska, Lincoln, Nebraska 68588 (United States)
  2. (United States)
  3. Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716 (United States)
Publication Date:
OSTI Identifier:
22412576
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 106; Journal Issue: 24; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ANISOTROPY; COBALT SILICIDES; INTERATOMIC DISTANCES; MAGNETIC MOMENTS; MAGNETIC PROPERTIES; MAGNETIZATION; MAGNETS; NANOPARTICLES; NANOSTRUCTURES; SPIN; SPIN ORIENTATION