Characterization of aluminum oxide tunnel barriers by combining transport measurements and transmission electron microscopy imaging
Journal article, 2014
We present two approaches for studying the uniformity of a tunnel barrier. The first approach is based on measuring single-electron and two-electron tunneling in a hybrid single-electron transistor. Our measurements indicate that the effective area of a conduction channel is about one order of magnitude larger than predicted by theoretical calculations. With the second method, transmission electron microscopy, we demonstrate that variations in the barrier thickness are a plausible explanation for the larger effective area and an enhancement of higher order tunneling processes.
Author
Thomas Aref
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
Aalto University
A. Averin
Aalto University
S. van Dijken
Aalto University
A. Ferring
Heidelberg University
M. Koberidze
Aalto University
V. F. Maisi
Centre for Metrology and Accreditation (MIKES)
Aalto University
Swiss Federal Institute of Technology in Zürich (ETH)
H.Q. Nguyend
Aalto University
Vietnam National University
R Nieminen
Aalto University
Jukka Pekola
Aalto University
Lide Yao
Aalto University
Journal of Applied Physics
0021-8979 (ISSN) 1089-7550 (eISSN)
Vol. 116 7 073702Subject Categories
Atom and Molecular Physics and Optics
Materials Chemistry
Condensed Matter Physics
DOI
10.1063/1.4893473