Cationic Disorder and Phase Segregation in LaAlO3/SrTiO3 Heterointerfaces Evidenced by Medium-Energy Ion Spectroscopy

Alexey Kalabukhov, Yu.A. Boikov, I.T. Serenkov, V.I. Sakharov, Vladimir Popok, R. Gunnarson, J. Borjesson, N. Ljustina, E. Olsson, Dag Winkler, Tord Claeson

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

115 Citationer (Scopus)
272 Downloads (Pure)

Abstract

Medium-energy ion spectroscopy (MEIS) has been used to study the depth profile and deduce the distribution of possible cationic substitutions in LaAlO3/SrTiO3 (LAO/STO) heterointerfaces. Analysis of La and Sr peaks in aligned and random MEIS spectra indicates that the surface layers of LAO on an STO substrate are not homogeneous and stoichiometric if the film thickness is less than 4 unit cell layers. This is possibly caused by a redistribution of La and Sr at the interface. Kelvin probe force microscopy reveals an inhomogeneous distribution of the surface potential in a 4 unit cell LAO film, indicating micrometersized regions of different compositions. Our findings provide a novel view on the microstructural origin of the electrically conductive interfaces.
OriginalsprogEngelsk
Artikelnummer146101
TidsskriftPhysical Review Letters
Vol/bind103
Udgave nummer14
Antal sider4
ISSN0031-9007
DOI
StatusUdgivet - 2 okt. 2009
Udgivet eksterntJa

Fingeraftryk

Dyk ned i forskningsemnerne om 'Cationic Disorder and Phase Segregation in LaAlO3/SrTiO3 Heterointerfaces Evidenced by Medium-Energy Ion Spectroscopy'. Sammen danner de et unikt fingeraftryk.

Citationsformater