Emergent Magnetism with Continuous Control in the Ultrahigh-Conductivity Layered Oxide PdCoO2
Matthew Brahlek1, Alessandro R Mazza1,2, Abdulgani Annaberdiyev3
1Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States.
Nano Letters
|August 1, 2023
Summary
Researchers can now precisely control magnetism in PdCoO2 using helium implantation and annealing. This breakthrough enables tunable ferromagnetism for advanced spintronic applications.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Spintronics
Background:
- Achieving continuously tunable magnetism is hindered by difficulties in systematically altering material properties like valence, spin, orbital degrees of freedom, and crystallographic geometry.
- Magnetic metastability in ultrahigh-conductivity, nonmagnetic layered oxides presents a potential avenue for external control.
Purpose of the Study:
- To demonstrate a method for externally controlling ferromagnetism in PdCoO2.
- To investigate the mechanisms behind tunable magnetism induced by ion implantation and annealing.
Main Methods:
- Utilizing low-energy helium implantation to induce local lattice distortions in PdCoO2.
- Employing annealing to erase induced magnetism and restore the pristine state.
- Analyzing the emergence and communication of magnetic moments through itinerant metal states.
Main Results:
- Ferromagnetism was successfully induced by helium implantation and reversibly erased by annealing in PdCoO2.
- Local lattice distortions created by helium implantation led to the emergence of net magnetic moments on transition metal sites.
- Communication of localized moments through itinerant metal states triggered percolated long-range ferromagnetism.
Conclusions:
- Continuous control over magnetism is achievable by targeting magnetic metastability in materials like PdCoO2.
- Helium implantation and annealing offer a precise method for tuning magnetic and magnetotransport properties.
- This approach is critical for developing advanced spintronic devices with tailored functionalities.
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