Spin Filtering with Surface-Active Helicene- and Twistacene-Based Perylene Diimides.

Area of Science:

• Molecular and macromolecular chemistry
• Spintronics
• Chiral materials science

Background:

• Chiral molecular systems offer potential for spin polarization in spintronics.
• Developing new materials with controllable spin properties is crucial for advanced electronic applications.

Purpose of the Study:

• To create novel optically active helical molecules for spintronics applications.
• To investigate the relationship between molecular chirality and spin-dependent conductivity.

Main Methods:

• Synthesis of perylene diimide-based twistacene and helicene helical ladder dimers.
• Scalable separation of enantiomers and functionalization with thiol groups.
• Formation of self-assembled monolayers on metal surfaces.
• Conductive atomic force microscopy to probe conductivity and spin-dependent transport.

Main Results:

• Demonstrated highly conductive self-assembled monolayers from chiral molecules.
• Showcased spin-polarized current controlled by the handedness of helical molecules on magnetized substrates.
• Observed a correlation between magnetic field-dependent conductivity and molecular helicity, independent of electronic circular dichroism sign.

Conclusions:

• Chiral perylene diimide-based helices enable spin-polarized electron transport.
• Molecular handedness can control current in spintronic devices.
• A link exists between molecular helicity and spin-dependent conductivity.