One-step fabrication of L1{sub 0} FePt nanocubes and rods by cluster beam deposition

Journal Article · Sun Apr 01 00:00:00 EDT 2012 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.3679085· OSTI ID:22038920

Akdogan, O; Li, W; Hadjipanayis, G C ^[1]; Skomski, R; Sellmyer, D J ^[2]

---

1. Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19711 (United States)
2. Department of Physics and Astronomy, University of Nebraska, Lincoln, Nebraska 68588 (United States)

In this work, single crystal L1{sub 0} FePt nanocubes have been successfully produced by a cluster beam deposition technique without the need of post annealing. Particles have been deposited by dc magnetron sputtering using high Ar pressures on both single crystal Si substrates and Au grids for the measurement of magnetic and structural properties, respectively. The nanocubes have a uniform size distribution with an average size of 5 nm. At 1 Torr, the particles have the L1{sub 0} structure with an order parameter of 0.5 and a RT coercivity of 2 kOe with high switching fields observed in the hysteresis loop. Further annealing increased the particle size to 20 nm and the RT coercivity to 10.2 kOe with perfect chemical ordering. In addition to these nanocubes, micron size rods with the L1{sub 0} structure have been observed near the cluster gun. SEM analysis showed that these rods consist of nanoparticles with 20 nm average size. Surfactant assisted high-energy ball milling has been used to separate the nanoparticles from the rods. After one hour of milling, these 20 nm particles showed a room temperature coercivity of 9 kOe with an order parameter of 0.85. These FePt nanocubes have a potential for use in the development of future high-density magnetic recording media because of their high coercivity, good shape and very narrow size distribution.

• OSTI ID: 22038920
• Journal Information: Journal of Applied Physics, Vol. 111, Issue 7; Conference: 55. annual conference on magnetism and magnetic materials, Atlanta, GA (United States), 14-18 Nov 2010; Other Information: (c) 2012 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
77 NANOSCIENCE AND NANOTECHNOLOGY
ANNEALING
CLUSTER BEAMS
COERCIVE FORCE
ENERGY BEAM DEPOSITION
HYSTERESIS
IRON ALLOYS
MONOCRYSTALS
MORPHOLOGY
NANOSTRUCTURES
ORDER PARAMETERS
PARTICLE SIZE
PARTICLES
PLATINUM ALLOYS
SCANNING ELECTRON MICROSCOPY
SILICON
SPUTTERING
SUBSTRATES
TEMPERATURE RANGE 0273-0400 K