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Updated: May 23, 2026
06:43
Writing and Low-Temperature Characterization of Oxide Nanostructures
Published on: July 18, 2014
Room temperature L1₀ phase transformation in binary CoPt nanostructures prepared by focused-electron-beam-induced
F Porrati1, E Begun, M Winhold
1Physikalisches Institut, Goethe-Universität, Max-von-Laue-Strasse 1, D-60438 Frankfurt am Main, Germany. porrati@physik.uni.frankfurt.de
Nanotechnology
|April 14, 2012
Summary
Focused-electron-beam-induced deposition created cobalt-platinum-carbon (CoPt-C) alloys. Electron irradiation transformed amorphous CoPt nanoparticles into ferromagnetic L1₀ nanocrystallites, tuning properties.
Area of Science:
- Materials Science
- Nanotechnology
- Physics
Background:
- CoPt-C binary alloys are promising for magnetic applications.
- Controlling the phase and magnetic properties of CoPt-C is crucial for device performance.
Purpose of the Study:
- To fabricate CoPt-C binary alloys using focused-electron-beam-induced deposition.
- To investigate the structural and magnetic transformations induced by low-energy electron irradiation.
- To tune the electrical and magneto-transport properties of the CoPt-C alloy.
Main Methods:
- Focused-electron-beam-induced deposition (FEBID) using Co₂(CO)₈ and (CH₃)₃CH₃C₅H₄Pt precursors.
- Transmission Electron Microscopy (TEM) for structural analysis.
- Room temperature low-energy electron irradiation for phase transformation and property tuning.
Main Results:
- CoPt nanoparticles embedded in a carbonaceous matrix were successfully fabricated.
- As-grown samples were amorphous; electron irradiation induced the formation of face-centered tetragonal L1₀ CoPt nanocrystallites.
- A transition from a superparamagnetic to a ferromagnetic state at room temperature was observed.
- Electrical and magneto-transport properties were continuously tunable by varying the irradiation dose.
Conclusions:
- Low-energy electron irradiation is an effective method for transforming amorphous CoPt-C into L1₀ ferromagnetic nanocrystallites.
- The process allows for controlled tuning of magnetic and transport properties at room temperature.
- This offers a pathway for developing advanced magnetic materials and devices.
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