Spin and Momentum Mapping of Highly Oriented Spinterfaces

Area of Science:

• Surface Science
• Condensed Matter Physics
• Materials Science

Background:

• Spinterfaces, interfaces between magnetic substrates and molecular layers, are crucial for spin-electronic devices.
• Understanding spin-polarized electron behavior at these interfaces is key to device design.

Purpose of the Study:

• To investigate how molecular order influences spin-polarized electron scattering at magnetic interfaces.
• To compare the effects of iron phthalocyanine (FePc) and metal-free phthalocyanine (H2Pc) on the electronic structure of an iron surface.

Main Methods:

• Spin-resolved momentum microscopy
• Photoemission tomography
• Assembly of molecular monolayers (FePc, H2Pc) on an oxygen-passivated iron surface.

Main Results:

• Long-range molecular order induces coherent Umklapp scattering of substrate electrons.
• Distinct Umklapp replicas of substrate valence bands were observed for both FePc and H2Pc lattices.
• Spin polarization near normal emission is dominated by scattering, not molecular orbitals.

Conclusions:

• Structural order in molecular layers significantly modifies the spin-resolved electronic structure at spinterfaces.
• Electron scattering, rather than direct molecular orbital contributions, governs interface spin polarization.
• Provides insights for engineering spinterfaces with tailored spin functionalities.