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DOE OSTI · 2340077

Electron Spin Polarization and Rectification Driven by Chiral Perylene Diimide-Based Nanodonuts

Ko, Chih-Hung·Zhu, Qirong·Bullard, George·Tassinari, Francesco·Morisue, Mitsuhiko·Naaman, Ron·Therien, Michael J.
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Abstract

The chirality-induced spin selectivity (CISS) effect allows thin-film layers of chiral conjugated molecules to function as spin filters at ambient temperature. Through solvent-modulated dropcasting of chiral l- and d-perylene diimide (PDI) monomeric building blocks, two types of aggregate morphologies, nanofibers and nanodonuts, may be realized. Spin-diode behavior is evidenced in the nanodonut structures. Stacked PDI units, which form the conjugated core of these nanostructures, dominate the nanodonut–Au electrode contact; in contrast, the AFM tip contacts largely the high-resistance solubilizing alkyl chains of the chiral monomers that form these nanodonuts. Current–voltage responses of the nanodonuts, measured by magnetic conductive AFM (mC-AFM), demonstrate substantial spin polarizations as well as spin current rectification ratios (>10) that exceed the magnitudes of those determined to date for other chiral nanoscale systems. Furthermore, these results underscore the potential for chiral nanostructures, featuring asymmetric molecular junctions, to enable CISS-based nanoscale spin current rectifiers.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYHeat transferNanostructuresPolarizationQuantum mechanicsThermodynamic modeling

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Ko, Chih-Hung, Zhu, Qirong, Bullard, George, Tassinari, Francesco, Morisue, Mitsuhiko, Naaman, Ron, Therien, Michael J.. 2023-11-08. Electron Spin Polarization and Rectification Driven by Chiral Perylene Diimide-Based Nanodonuts. https://doi.org/10.1021/acs.jpclett.3c02722

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