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Published on: February 7, 2017
Chirality Induced Odd-Even Spin Selectivity in Self-Assembled Peptide-Based Helical Nanofibers
Nidhi Bhatt1, Rabia Garg1, Tapan Kumar Das2
1Institute of Nano Science and Technology (INST), Mohali, Sector 81, Sahibzada Ajit Singh Nagar, Mohali 140306, Punjab, India.
ACS Nano
|June 2, 2026
Summary
Chirality-induced spin selectivity (CISS) in peptide nanofibers shows an odd-even effect based on spacer length. This demonstrates achiral segments can influence spin selectivity in chiral materials.
Area of Science:
- Spintronics
- Organic electronics
- Chirality and spin physics
Background:
- Chirality-induced spin selectivity (CISS) is crucial for spintronics, enabling spin polarization in chiral molecules.
- Previous CISS studies focused on intrinsic chirality or chiral solvents, lacking evidence for achiral segments driving the effect.
- Peptide-based helical nanofibers offer a novel platform to explore CISS phenomena.
Purpose of the Study:
- To experimentally investigate the CISS effect in peptide-based helical nanofibers.
- To demonstrate that achiral segments within a chiral molecule can influence spin selectivity.
- To explore the impact of spacer length and solvent ratio on spin-dependent transport.
Main Methods:
- Fabrication and characterization of peptide-based helical nanofibers with varying achiral spacer lengths.
- Magnetic-field-dependent atomic force microscopy (mc-AFM) and Kelvin probe force microscopy (KPFM) for spin selectivity analysis.
- Construction of a spin-valve device to validate spin-dependent transport properties.
Main Results:
- Observation of a distinct odd-even effect in spin selectivity, dependent on the number of methylene spacers.
- Demonstration of tunable spin selectivity by altering achiral spacer length.
- Correlation between mc-AFM/KPFM findings and spin-valve device performance, validating the CISS effect.
- Investigation into the role of achiral solvent ratio on spin-dependent transport.
Conclusions:
- Achiral segments in chiral molecules can effectively drive the CISS effect in peptide-based nanofibers.
- The odd-even effect provides a new mechanism for controlling spin selectivity in chiral organic materials.
- These findings open new avenues for designing chiral organic materials for spintronic applications.
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