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Tunneling magnetoresistance from a symmetry filtering effect
1Center for Materials for Information Technology and Department of Physics, University of Alabama, AL, USA.
Science and Technology of Advanced Materials
|November 24, 2016
Summary
Spintronics utilizes electron spin for data storage. Fe-MgO-Fe barriers enable spin filtering, leading to significant tunneling magnetoresistance for hard drive sensors and magnetic memory.
Area of Science:
- Spintronics
- Materials Science
- Quantum Mechanics
Background:
- Spintronics is an emerging field leveraging electron spin for electronic devices.
- Understanding electron behavior in magnetic tunnel junctions is crucial for technological advancement.
Approach:
- Investigated electron tunneling through magnesium oxide (MgO) insulators.
- Explored symmetry filtering of electron wavefunctions.
- Utilized epitaxial ferromagnetic electrodes (Fe) with specific symmetries.
Key Points:
- Certain electron wavefunction symmetries are preferentially transmitted through MgO insulators.
- Epitaxial ferromagnetic electrodes with matching 2D symmetry enable spin filtering.
- Fe-MgO-Fe barriers exhibit spin-dependent wavefunction transmission.
Conclusions:
- A large tunneling magnetoresistance (TMR) effect is achieved in Fe-MgO-Fe structures.
- This TMR effect is vital for read sensors in hard disk drives.
- Spintronics holds promise for next-generation magnetic memory technologies.
Keywords:
TMRcomplex energy banddelta-1 stateevanescent stateinterfacial resonance statesmagnetic tunnel junctionsymmetry filtertunneling magnetoresistanceMore Related Videos
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