Fig. 4: Interfacial layer formation.
From: Engineering of Fe-pnictide heterointerfaces by electrostatic principles

a STEM brightfield (BF) image of the Sm-1111/IFL/Ba-122 cross-section. The roughness of the IFL is visible in the contrast. b HR-STEM BF image of the IFL showing crystalline structures. c EDS analysis with As L, O K, Sm L, Fe K, and Ba L maps confirms the presence of O, Sm, and Fe in the IFL. Horizontal lines mark the IFL region.