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Observation of the Nonreciprocal Magnon Hanle Effect
Janine Gückelhorn1,2, Sebastián de-la-Peña3, Monika Scheufele1,2
1Walther-Meißner-Institut, Bayerische Akademie der Wissenschaften, D-85748 Garching, Germany.
Physical Review Letters
|June 9, 2023
Summary
Researchers observed a nonreciprocal magnon Hanle effect in hematite, controllable by magnetic fields. This discovery in antiferromagnetic insulators offers new possibilities for spintronic devices and fundamental physics research.
Area of Science:
- Condensed Matter Physics
- Spintronics
- Materials Science
Background:
- The magnon Hanle effect arises from magnon pseudospin precession in antiferromagnets.
- Electrical detection of spin transport in antiferromagnetic insulators is crucial for spintronic devices.
Purpose of the Study:
- To investigate nonreciprocity in the magnon Hanle effect in hematite.
- To explore the potential of hematite for spintronic applications and fundamental studies.
Main Methods:
- Electrical spin injection and detection using platinum electrodes in hematite films.
- Measurement of the magnon Hanle signal under varying magnetic fields.
Main Results:
- Observed a nonreciprocal Hanle signal dependent on the roles of platinum electrodes (injector/detector).
- The nonreciprocity varied with the applied magnetic field and reversed sign at the compensation field.
- Explained the nonreciprocity by a spin transport direction-dependent pseudofield.
Conclusions:
- The study demonstrates a controllable nonreciprocal magnon Hanle effect in hematite.
- This finding opens avenues for exotic physics in antiferromagnets and potential spintronic device applications.
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