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Sensing the Local Magnetic Environment through Optically Active Defects in a Layered Magnetic Semiconductor
Julian Klein1, Zhigang Song2,3, Benjamin Pingault2,4
1Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts02139, United States.
ACS Nano
|December 20, 2022
Summary
Atomic defects in van der Waals (vdW) magnets like CrSBr act as probes of local magnetic environments. These optically active defects reveal defect-induced magnetic order, paving the way for novel quantum technologies.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Technologies
Background:
- Atomic-level defects in van der Waals (vdW) materials are crucial for quantum technologies.
- CrSBr, a layered magnetic semiconductor, offers a direct gap and complex magnetic phase diagram, making it ideal for studying optically active defects.
Purpose of the Study:
- To investigate optically active defects in CrSBr.
- To understand the relationship between these defects and the material's magnetic order.
- To explore the potential of vdW magnets for defect-based quantum applications.
Main Methods:
- Optical spectroscopy to observe defect emission.
- Correlation analysis between defect emission and bulk/defect-induced magnetic order.
- Theoretical elucidation of exchange coupling effects.
Main Results:
- Observation of spectrally narrow (1 meV) defect emission in CrSBr.
- Correlation of defect emission with both bulk magnetic order and a low-temperature, defect-induced magnetic order.
- Elucidation of the origin of defect-induced magnetic order via local and nonlocal exchange coupling.
Conclusions:
- CrSBr serves as an exceptional platform for optically studying defects correlated with the magnetic lattice.
- Controlled defect engineering in vdW magnets can create tailored magnetic textures and phases with optical access.
- This research advances the development of quantum sensing and quantum technologies using defect-engineered magnetic materials.
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