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Demonstration of Spin-Multiplexed and Direction-Multiplexed All-Dielectric Visible Metaholograms
Published on: September 25, 2020
Electrically driven magnetization of diluted magnetic semiconductors actuated by the Overhauser effect
L Siddiqui1, A N M Zainuddin, S Datta
1School of Electrical and Computer Engineering, Purdue University, West Lafayette, IN 47907, USA. lsiddiqu@purdue.edu
Summary
Altering electron spin populations in diluted magnetic semiconductors (DMS) can control magnetization. A small imbalance in quasi-Fermi levels mimics a strong magnetic field, offering new control pathways for DMS materials.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Spintronics
Background:
- Magnetization in diluted magnetic semiconductors (DMS) is tunable via hole density.
- Controlling Curie temperature and magnetization is crucial for DMS applications.
Purpose of the Study:
- To investigate magnetization control in DMS by manipulating quasi-Fermi levels.
- To explore an alternative to external magnetic fields for tuning DMS properties.
Main Methods:
- Coupling mean-field theory of DMS ferromagnetism with master equations for Mn spin dynamics.
- Theoretical modeling of quasi-Fermi level splitting effects on Mn spin polarization.
Main Results:
- A small splitting (0.1 meV) of up-spin and down-spin quasi-Fermi levels can simulate a 1 T magnetic field.
- This effect is significant when spin-lattice relaxation is negligible.
- The physics is analogous to the Overhauser effect, with Mn impurities acting as nuclei.
Conclusions:
- Quasi-Fermi level splitting offers a novel method for controlling magnetization in DMS.
- Proposed lateral spin-valve structures can experimentally demonstrate this effect.
- This provides a new avenue for spintronic device development.
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