Distance- and spin-resolved spectroscopy of iridium atoms on an iron bilayer

Abstract

The induced spin polarization of Ir atoms on a ferromagnetic Fe double layer on W(110) has been investigated with spin-polarized scanning tunneling microscopy. An unoccupied state is observed with a spin polarization exceeding 60 % that is inverted with respect to the Fe layer. This inversion is due to the tunneling gap acting as an orbital and spin filter. Distance dependent measurements show that the spin polarization remains approximately constant over the entire experimentally accessible range, from far in the tunneling regime to 1Å from the point of contact formation. This is corroborated by density functional theory calculations which show that the inversion of spin polarization occurs within 0.5Å of the adatom.

Quantifying exchange forces of a spin spiral on the atomic scale

“…Within the Tersoff-Hamann model of STM [41,42], the differential conductance is proportional to the LDOS a few Å above the surface, and the asymmetry curves in spin-polarized measurements ( Fig. 2(f,g)) can be compared to the spin polarization of the vacuum LDOS [43,44]. As shown in the supplemental material ( Fig.…”