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Sample Preparation using a Lipid Monolayer Method for Electron Crystallographic Studies
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Chirality-Dependent Electron Spin Filtering by Molecular Monolayers of Helicenes
Matthias Kettner1, Volodymyr V Maslyuk2, Daniel Nürenberg1
1Center for Soft Nanoscience and Physikalisches Institut , University of Münster , 48149 Münster , Germany.
The Journal of Physical Chemistry Letters
|April 6, 2018
Summary
Low-energy electrons interacting with helical heptahelicene molecules show spin polarization. This spin selectivity is linked to the molecule's helical structure, offering insights into spin-dependent electron transport.
Area of Science:
- Molecular physics
- Surface science
- Organic electronics
Background:
- Chiral organic molecules on surfaces are crucial for spintronics.
- Understanding electron spin interactions with molecular helices is key to developing new electronic devices.
Purpose of the Study:
- To investigate the spin polarization of photoelectrons transmitted through heptahelicene monolayers.
- To explore the relationship between molecular helicity and electron spin transmission.
Main Methods:
- Experimental study of low-energy photoelectron interaction with heptahelicene monolayers on metal surfaces.
- Theoretical analysis using spin-resolved density functional theory (DFT) and a model Hamiltonian approach.
Main Results:
- Preferential transmission of one spin component observed for photoelectrons interacting with heptahelicene.
- Longitudinal spin polarization excess of 6-8% achieved for transmitted electrons.
- Correlation established between spin polarization and the helical sense of heptahelicene molecules.
Conclusions:
- The helical structure of heptahelicene induces spin polarization in transmitted electrons.
- Spin-orbit coupling within the molecule's electrostatic potential governs this spin-dependent transport.
- Results support a semiclassical model of electron transport along helical pathways.
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