Full Electroresistance Modulation in a Mixed-Phase Metallic Alloy.
1Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
Researchers achieved a giant electroresistance effect in a metallic alloy above room temperature using an electric field. This was enabled by strain-mediated magnetoelectric coupling in iron-rhodium/barium titanate heterostructures, leading to a magnetic phase transition.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Magnetism
Background:
- Iron-rhodium (FeRh) alloys exhibit a temperature-driven magnetic phase transition.
- Magnetoelectric coupling offers a pathway to control magnetic properties with electric fields.
Purpose of the Study:
- To investigate the electroresistance effect in FeRh/BaTiO3 heterostructures.
- To demonstrate electric-field-induced magnetic phase transitions above room temperature.
Main Methods:
- Epitaxial growth of FeRh/BaTiO3 heterostructures.
- Application of electric fields to induce piezoelectric strain.
- Measurement of electroresistance and magnetic properties.
Main Results:
- A giant, approximately 22%, electroresistance modulation was observed above room temperature.
- The effect was achieved using a low electric field (2 kV/cm) via strain-mediated magnetoelectric coupling.
- An isothermal magnetic phase transition in FeRh thin films was driven by tetragonality modulation, distinct from temperature-driven transitions.
Conclusions:
- FeRh/BaTiO3 heterostructures exhibit significant electric-field-controlled electroresistance.
- This work provides evidence for strain-induced isothermal magnetic phase transitions in FeRh.
- FeRh serves as a model system for studying phase instability in materials with colossal magnetoresistance properties.
More Related Videos
09:49In Situ Transmission Electron Microscopy with Biasing and Fabrication of Asymmetric Crossbars Based on Mixed-Phased a-VOx
Published on: May 13, 2020
12:02Determination of Thermodynamic Properties of Alkaline Earth-liquid Metal Alloys Using the Electromotive Force Technique
Published on: November 3, 2017
Related Concept Videos
Electrochemical Systems
Biasing of Metal-Semiconductor Junctions
In Schottky junctions, where the semiconductor is n-type, applying a positive voltage to the metal relative to the semiconductor reduces its Fermi...
Metal-Semiconductor Junctions
Schottky Barriers
Schottky barriers arise when a metal with a work function (Φm) contacts a semiconductor with a different work function (Φs). Initially, electrons transfer until the Fermi levels of the metal and semiconductor align at equilibrium. For instance, if Φm > Φs, the semiconductor Fermi level is higher than the metal's before contact. The...
The Electrical Double Layer
