Strain-induced properties of epitaxial VOx thin films
University of Groningen, Materials Science Centre,
Nijenborgh 4, 9747 AG, Groningen, The Netherlands
Corresponding author: a email@example.com
Published online: 25 February 2005
We have grown VOx thin films on different substrates in order to investigate the influence of epitaxial strain on the transport properties. We found that the electric conductivity is much larger for films grown under compressive strain on SrTiO3 substrates, as compared to bulk material and VOx films grown under tensile strain on MgO substrates. A clear crossover from metallic to semiconducting behavior is observed when increasing the oxygen content x. Apparently, the application of strain induces a Mott-Hubbard insulator-to-metal transition in VO. The VOx/SrTiO3 films show an unexpected large positive magnetoresistance effect at low temperatures, which is not found in the VOx films grown under tensile strain on MgO or on a substrate with a similar lattice parameter.
PACS: 68.55.-a – Thin film structure and morphology / 61.10.-i – X-ray diffraction and scattering / 73.50.-h – Electronic transport phenomena in thin films
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2005