Insulator at the Ultrathin Limit: MgO on Ag(001)

Silvia Schintke; Stéphane Messerli; Marina Pivetta; François Patthey; Laurent Libioulle; Massimiliano Stengel; Alessandro De Vita; Wolf-Dieter Schneider

doi:10.1103/PhysRevLett.87.276801

Insulator at the Ultrathin Limit: MgO on Ag(001)

Silvia Schintke, Stéphane Messerli, Marina Pivetta, François Patthey, Laurent Libioulle, Massimiliano Stengel, Alessandro De Vita, and Wolf-Dieter Schneider

Phys. Rev. Lett. 87, 276801 – Published 7 December 2001

Abstract

The electronic structure and morphology of ultrathin MgO films epitaxially grown on Ag(001) were investigated using low-temperature scanning tunneling spectroscopy and scanning tunneling microscopy. Layer-resolved differential conductance ( $d I / d U$ ) measurements reveal that, even at a film thickness of three monolayers, a band gap of about 6 eV is formed corresponding to that of the MgO(001) single-crystal surface. This finding is confirmed by layer-resolved calculations of the local density of states based on density functional theory.

Received 21 January 2000

DOI:https://doi.org/10.1103/PhysRevLett.87.276801

Authors & Affiliations

Silvia Schintke¹, Stéphane Messerli¹, Marina Pivetta¹, François Patthey¹, Laurent Libioulle¹, Massimiliano Stengel², Alessandro De Vita^2,3, and Wolf-Dieter Schneider¹

¹Institut de Physique de la Matière Condensée, Université de Lausanne, CH-1015 Lausanne, Switzerland
²Institut Romand de Recherche Numérique en Physique des Matériaux, PHH-Ecublens, CH-1015 Lausanne, Switzerland
³INFM and Dipartimento di Ingegneria dei Materiali, Università di Trieste, via A. Valerio 2, 34127 Trieste, Italy