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Improved spin-orbit torque induced magnetization switching efficiency by helium ion irradiation
Suhyeok An1, Eunchong Baek1, Jin-A Kim1
1Department of Emerging Materials Science, DGIST, Daegu, 42988, Korea.
Scientific Reports
|March 3, 2022
Summary
Helium ion irradiation reduces spin-orbit torque (SOT) switching current in spintronics devices. This is due to improved spin Hall angle and reduced interface anisotropy, paving the way for efficient SOT device engineering.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Electrical Engineering
Background:
- Spin-orbit torque (SOT) is crucial for advanced spintronics applications like non-volatile memory.
- Reducing SOT switching current is key to improving device efficiency and power consumption.
- Previous studies on helium ion irradiation for SOT focused on observed effects, not underlying mechanisms.
Purpose of the Study:
- To investigate the origins of SOT switching current reduction induced by helium ion irradiation.
- To analyze the impact of ion irradiation on material properties and interfacial characteristics.
- To establish a relationship between irradiation parameters and device performance.
Main Methods:
- Helium ion irradiation of heavy metal/ferromagnet layers.
- Measurement and analysis of SOT switching current.
- Characterization of material resistivity and interfacial properties.
- Calculation of power consumption based on derived parameters.
Main Results:
- Helium ion irradiation significantly reduced the SOT switching current.
- Improved spin Hall angle and reduced surface anisotropy energy were identified as primary reasons.
- A near-linear correlation was observed between changes in spin Hall angle and platinum resistivity.
- Power consumption decreased with increasing ion irradiation dosage.
Conclusions:
- Helium ion irradiation effectively reduces SOT switching current by altering material and interfacial properties.
- The findings provide a mechanistic understanding of ion irradiation effects on SOT.
- This research offers a pathway for engineering superior SOT devices using helium ion irradiation.
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