Determination of interface atomic structure and its impact on spin transport using Z-contrast microscopy and density-functional theory.
We combine Z-contrast scanning transmission electron microscopy with density-functional-theory calculations to determine the atomic structure of the interface in spin-polarized light-emitting diodes. A 44% increase in spin-injection efficiency occurs after a low-temperature anneal, which produces an ordered, coherent interface consisting of a single atomic plane of alternating Fe and As atoms. First-principles transport calculations indicate that the increase in spin-injection efficiency is due to the abruptness and coherency of the annealed interface.
Zega
Thomas J
TJ
Naval Research Laboratory, Washington, DC 20375, USA.
Hanbicki
Aubrey T
AT
Erwin
Steven C
SC
Zutić
Igor
I
Kioseoglou
George
G
Li
Connie H
CH
Jonker
Berend T
BT
Stroud
Rhonda M
RM