Kelvin Probe Force Microscopy Study of LaAlO3/SrTiO3 Heterointerfaces
Artikel i vetenskaplig tidskrift, 2010

Surface potential distributions in ultra-thin (0.8-3.9 nm) LaAlO3 layers deposited on SrTiO3 substrates are studied. It is found that the potential distribution evolves from island-like to a homogeneous one with increasing LaAlO3 thickness. It is suggested that the observed islands are caused by a locally enhanced concentration of mobile charge carriers at the interface that is, in turn, related to non-stoichiometry of the layers with thickness bellow 4 unit cells. Transition to a homogeneous potential distribution with increasing LAO thickness (≥4 unit cells) corresponds to the formation of a quasi-2-dimensional electron gas. The results agree with a percolation model explaining the insulator-to-metal transition that occurs at the LaAlO3/SrTiO3 heterointerface.

LaAlO 3/SrTiO 3 Heterointerface

Kelvin Probe Force Microscopy

Författare

Vladimir Popok

Göteborgs universitet

Alexei Kalaboukhov

Chalmers, Mikroteknologi och nanovetenskap (MC2), Kvantkomponentfysik

Robert Gunnarsson

Chalmers, Mikroteknologi och nanovetenskap (MC2), Tillämpad kvantfysik

Segey Lemeshko

Chalmers University of Technology

Tord Claeson

Chalmers, Mikroteknologi och nanovetenskap (MC2), Kvantkomponentfysik

Dag Winkler

Chalmers, Mikroteknologi och nanovetenskap (MC2)

Journal of Advanced Microscopy Research

2156-7573 (ISSN) 2156-7581 (eISSN)

Vol. 5 26-30

Styrkeområden

Nanovetenskap och nanoteknik

Materialvetenskap

Ämneskategorier

Övrig annan teknik

Den kondenserade materiens fysik

DOI

10.1166/jamr.2010.1020