Organic Monolayer Protected Topological Surface State.

Perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA)/Bi2Se3 and Fe/PTCDA/Bi2Se3 heterointerfaces are investigated using scanning tunneling microscopy and spectroscopy. The close-packed self-assembled PTCDA monolayer possesses big molecular band gap and weak molecule-substrate interactions, which leaves the Bi2Se3 topological surface state intact under PTCDA. Formation of Fe-PTCDA hybrids removes interactions between the Fe dopant and the Bi2Se3 surface, such as doping effects and Coulomb scattering.

Spin-Dependent Molecule Symmetry at a Pentacene-Co Spinterface.

Incorporating spin-polarized scanning tunneling microscopy (SP-STM) measurements and first-principles calculations, we resolve spin-polarized states and consequent features in a pentacene(PEN)-Co hybrid system. Symmetry reduction of PEN clarifies the PEN adsorption site and the Co stacking methods. Near the Fermi energy, the molecular symmetry is spin-dependently recovered and an inversion of spin-polarization in PEN with respect to Co is observed.

Digitized charge transfer magnitude determined by metal-organic coordination number.

Well-ordered metal-organic nanostructures of Fe-PTCDA (perylene-3,4,9,10-tetracarboxylic-3,4,9,10-dianhydride) chains and networks are grown on a Au(111) surface. These structures are investigated by high-resolution scanning tunneling microscopy. Digitized frontier orbital shifts are followed in scanning tunneling spectroscopy.