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Published on: June 28, 2018
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Chiral Mesostructured NiO Films with Spin Polarisation.
Te Bai1, Jing Ai2, Liyang Liao3
1School of Chemistry and Chemical Engineering, State Key Laboratory of Metal Matrix Composites, Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, P.R. China.
Angewandte Chemie (International Ed. in English)
|February 8, 2021
Summary
Chiral mesostructured NiO films exhibit spin polarization due to their unique structure. This discovery offers new possibilities for controlling spin in functional inorganic materials.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Centrosymmetric nonferromagnetic crystals typically lack spin polarization.
- Chiral molecules can induce symmetry-breaking effects in material fabrication.
- Understanding spin behavior in novel materials is crucial for spintronics.
Purpose of the Study:
- To investigate the presence and origin of spin polarization in chiral mesostructured NiO films (CMNFs).
- To explore the relationship between chirality and spin polarization in these materials.
- To provide insights into directional spin control mechanisms.
Main Methods:
- Fabrication of CMNFs using a chiral molecule to break symmetry.
- Characterization of spin polarization using chirality-dependent magnetic-tip conducting atomic force microscopy (mc-AFM).
- Confirmation of spin polarization via magnetic field-independent magnetic circular dichroism (MCD).
Main Results:
- Spin polarization was confirmed in centrosymmetric nonferromagnetic CMNFs.
- Two levels of chirality were identified: twisted nanoflakes and helical stacking.
- Chirality-dependent effective magnetic fields, generated by electron transfer, were proposed as the mechanism.
Conclusions:
- Asymmetric spin-orbit coupling (SOC) induced by effective magnetic fields selectively controls spin motion.
- The findings offer fundamental insights into directional spin control.
- This research opens avenues for developing unprecedented functional inorganic materials for spintronic applications.
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