When imaged by scanning tunneling microscopy (STM) at constant current under nontopographic conditions, nanosized MgO islands grown on Ag(100) may show a fractal dark internal structure and/or appear embedded in the surface. On the contrary, when imaged under topographic conditions, the same islands appear as nearly flat plateaus. Islands showing different contrast and a different contrast dependence on sample bias have been often reported in the literature, but a thorough explanation is still missing. Here we demonstrate, on the basis of of experimental data and computational results, that such structure is due to the accumulation of oxygen at the MgO islandssubstrate interface. Interestingly, interfacial oxygen concentrates at the center of the islands.

Interface Oxygen Induced Internal Structures of Ultrathin MgO Islands Grown on Ag(100)

Vattuone, Luca;Rocca, Mario Agostino
2020-01-01

Abstract

When imaged by scanning tunneling microscopy (STM) at constant current under nontopographic conditions, nanosized MgO islands grown on Ag(100) may show a fractal dark internal structure and/or appear embedded in the surface. On the contrary, when imaged under topographic conditions, the same islands appear as nearly flat plateaus. Islands showing different contrast and a different contrast dependence on sample bias have been often reported in the literature, but a thorough explanation is still missing. Here we demonstrate, on the basis of of experimental data and computational results, that such structure is due to the accumulation of oxygen at the MgO islandssubstrate interface. Interestingly, interfacial oxygen concentrates at the center of the islands.
File in questo prodotto:
File Dimensione Formato  
acs.jpcc.0c01248_124_2020.pdf

accesso chiuso

Tipologia: Documento in versione editoriale
Dimensione 8.67 MB
Formato Adobe PDF
8.67 MB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11567/1005057
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 4
  • ???jsp.display-item.citation.isi??? 4
social impact