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Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
Magnetic anisotropy tuning in room temperature ferromagnet Ca2FeMoO6
Wakeel Ahmad1, Pranjul Garg2, Dipak Sahu1
1Department of Physics, Indian Institute of Technology, Kanpur 208016, India.
Summary
Strain engineering precisely controls magnetic anisotropy in room-temperature ferromagnetic CaFeMoO. Tensile strain reorients the easy axis, demonstrating strong magnetoelastic coupling (MEC) in this double perovskite material.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Magnetism
Background:
- Magnetic anisotropy is crucial for magnetic applications and is tunable via chemical substitution, shape engineering, defect manipulation, and strain.
- Room-temperature ferromagnetic materials are highly sought after for technological advancements.
Purpose of the Study:
- To demonstrate and investigate strain-mediated control of magnetic anisotropy in CaFeMoO.
- To explore the role of magnetoelastic coupling (MEC) in inducing anisotropy reorientation.
Main Methods:
- Fabrication of CaFeMoO thin films on substrates to induce tensile strain.
- Experimental measurement of magnetic anisotropy constants.
- Micromagnetic simulations to support experimental findings.
Main Results:
- Tunable magnetic anisotropy from in-plane to out-of-plane (180 kJ/m³) using 0.9% tensile strain.
- Negative magnetostriction in CaFeMoO promotes out-of-plane anisotropy via MEC.
- Experimental results are corroborated by micromagnetic simulations.
Conclusions:
- Modest tensile strain effectively reorients the easy magnetic axis in CaFeMoO.
- Strong magnetoelastic coupling (MEC) is key to achieving strain-induced anisotropy changes in this double perovskite.
- Strain engineering offers a viable route for tuning magnetic properties in CaFeMoO.
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