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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
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Electrostatically controlled spin polarization in Graphene-CrSBr magnetic proximity heterostructures
Boxuan Yang1, Bibek Bhujel2, Daniel G Chica3
1Zernike Institute for Advanced Materials, University of Groningen, 9747, AG, Groningen, The Netherlands. boxuan.yang@rug.nl.
Nature Communications
|May 25, 2024
Summary
Graphene interfaced with CrSBr exhibits tunable spin polarization without a magnetic field, enabling spintronics applications. This breakthrough demonstrates electrostatic control over spin currents in graphene.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Spintronics
Background:
- The magnetic proximity effect can induce spin-dependent exchange shifts in graphene's band structure.
- This effect leads to magnetization and spin polarization of charge carriers, crucial for spintronics.
- Electrostatic control of spin polarization in graphene has remained a significant challenge.
Purpose of the Study:
- To demonstrate the electrostatic control of spin polarization in graphene.
- To investigate the effects of interfacing graphene with the van der Waals antiferromagnet CrSBr.
- To explore the potential for graphene-based spintronic devices.
Main Methods:
- Interfacing graphene with the van der Waals antiferromagnet CrSBr.
- Observing and analyzing the quantum Hall effect.
- Measuring the exchange shift and spin polarization of charge carriers.
Main Results:
- An unconventional quantum Hall effect attributed to counterflowing spin-polarized edge channels was observed.
- An exchange shift of 27–32 meV was extracted.
- An electrostatically tunable spin polarization in graphene, ranging from -50% to +69%, was achieved without an external magnetic field.
Conclusions:
- The study provides a proof of principle for electrostatically controlling spin polarization in graphene.
- This system serves as a tunable source of spin current, with potential applications in gate-tunable spin valve devices.
- The findings open new avenues for developing advanced spintronic devices utilizing graphene.
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