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Colossal angular magnetoresistance in ferrimagnetic nodal-line semiconductors
Junho Seo1,2, Chandan De1,3, Hyunsoo Ha4
1Center for Artificial Low Dimensional Electronic Systems, Institute for Basic Science (IBS), Pohang, Korea.
Nature
|November 25, 2021
Summary
Researchers discovered colossal angular magnetoresistance in magnetic nodal-line semiconductors. This effect, exceeding a trillion percent per radian, enables highly sensitive spintronic devices by tuning electronic conduction with magnetic fields.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Spintronics
Background:
- Efficient magnetic control of electronic conduction is crucial for spintronic applications like memory and logic.
- Topological band crossings in magnets offer a tunable platform for modulating electronic conduction via spin configurations.
Purpose of the Study:
- To investigate the potential of topological nodal-line degeneracy in magnetic semiconductors for large magnetotransport responses.
- To demonstrate colossal angular magnetoresistance in a model system and explore its implications for spintronics.
Main Methods:
- Theoretical proposal of colossal angular magnetoresistance in magnetic nodal-line semiconductors.
- Experimental investigation using a layered ferrimagnet, Mn3Si2Te6, and its derived compounds as a model system.
- Analysis of the lifting of topological band degeneracy by spin orientation and its effect on magnetotransport.
Main Results:
- Demonstrated that topological nodal-line degeneracy in magnetic semiconductors induces an extremely large angular response of magnetotransport.
- Observed a metal-insulator transition within the same ferrimagnetic phase due to the lifting of band degeneracy.
- Quantified the colossal angular magnetoresistance, exceeding a trillion percent per radian, in the model system.
Conclusions:
- Magnetic nodal-line semiconductors are a promising platform for achieving unprecedented sensitivity in spin- and orbital-dependent functionalities.
- The colossal angular magnetoresistance effect opens new avenues for advanced spintronic device design and applications.
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