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Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
Linear positive magnetoresistance and quantum interference in ferromagnetic metals
A Gerber1, I Kishon, I Ya Korenblit
1Raymond and Beverly Sackler Faculty of Exact Sciences, School of Physics and Astronomy, Tel Aviv University, Ramat Aviv 69978, Tel Aviv, Israel.
Physical Review Letters
|August 7, 2007
Summary
Geometrically constrained ferromagnets exhibit positive, linear magnetoresistance up to 60 T. Resistivity shows a minimum at 92 K, explained by quantum electron-electron interaction theory, though quantitative agreement is limited.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Mechanics
Background:
- Magnetoresistance in ferromagnetic materials is a key area of research.
- Understanding electron transport phenomena in constrained geometries is crucial for device applications.
Purpose of the Study:
- To investigate the magnetoresistance properties of geometrically constrained ferromagnets.
- To explore the temperature dependence of resistivity and its relation to quantum theories.
- To analyze the role of quantum electron-electron interactions in observed phenomena.
Main Methods:
- Measurements of magnetoresistance in fields up to 60 Tesla.
- Resistivity measurements as a function of temperature.
- Application of a modified quantum electron-electron interaction theory for explanation.
Main Results:
- Observed positive, linear, and isotropic magnetoresistance in iron, nickel, and cobalt thin films and granular mixtures.
- Resistivity minimum at 92 K, followed by logarithmic dependence at low temperatures.
- Qualitative agreement between experimental data and the modified quantum theory, with larger observed magnetoresistance slope.
Conclusions:
- Geometrically constrained ferromagnets display unique magnetoresistance characteristics.
- The quantum electron-electron interaction theory provides a basis for understanding these properties.
- Further theoretical refinement is needed to match the observed magnetoresistance magnitude.
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