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Non-uniform superlattice magnetic tunnel junctions
Sabarna Chakraborti1, Abhishek Sharma1
1Department of Electrical Engineering, Indian Institute of Technology Ropar, Nangal Rd, Hussainpur, Rupnagar, Punjab 140001, India.
Nanotechnology
|January 27, 2023
Summary
We introduce non-uniform superlattice magnetic tunnel junctions (Nu-SLTJs) offering enhanced TMR and faster switching. These novel devices promise significant advancements for next-generation spintronics.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- Magnetic tunnel junctions (MTJs) are key components in spintronic devices.
- Improving tunnel magnetoresistance (TMR) and switching speed is crucial for device performance.
- Non-uniform superlattices offer potential for novel electronic and magnetic properties.
Purpose of the Study:
- To propose and investigate a new class of non-uniform superlattice magnetic tunnel junctions (Nu-SLTJs).
- To explore the impact of various non-uniform profiles on TMR and switching characteristics.
- To predict the potential of Nu-SLTJs for high-performance spintronic applications.
Main Methods:
- Atomistic non-equilibrium Green's function (NEGF) formalism.
- Landau-Lifshitz-Gilbert-Slonczewski (LLGS) equation for spin transfer torque dynamics.
- Analysis of current-voltage characteristics, including negative differential resistance (NDR).
Main Results:
- Demonstrated significant enhancement in TMR (10^4-10^6%) and suppression of switching bias (≈9 folds) in Nu-SLTJs.
- Predicted ultrafast spin transfer torque switching speeds in the hundreds of picoseconds.
- Designed minimal three-barrier Nu-SLTJs with high TMR (≈10^4%) and large spin current for easier fabrication.
Conclusions:
- Nu-SLTJs represent a promising platform for next-generation spintronic devices.
- The proposed Nu-SLTJs offer a pathway to overcome limitations of current spintronic technologies.
- Further exploration of non-uniform superlattices is encouraged for advanced device design.
Keywords:
broad-band spin filteringmagnetic tunnel junctionresonant tunnelingspin transfer torquetunnel magnetoresistanceMore Related Videos
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