Optical waveguiding in magnetron-sputtered Na0.5K0.5NbO3 thin films on sapphire substrates
2003 (English)In: Applied Physics Letters, ISSN 0003-6951, E-ISSN 1077-3118, Vol. 82, no 3, 439-441 p.Article in journal (Refereed) Published
Preferentially oriented perovskite-structured Na0.5K0.5NbO3 (NKN) thin films have been deposited on hexagonal Al2O3(01 (1) under bar2) substrates using rf magnetron sputtering of a stoichiometric, high-density, ceramic target. Structural and film surface properties were measured using x-ray diffraction and atomic force microscopy, respectively. Optical and waveguiding properties were characterized using a prism-coupling technique. We observed sharp and distinguishable TM and TE propagation modes and measured the refractive index of NKN thin films of different thicknesses. The ordinary and extraordinary refractive indices were calculated to be n(o)=2.247+/-0.002 and n(e)=2.216+/-0.002 for a 2.0-mum-thick film at 632.8 nm. This implies a birefringence Deltan=n(e)-n(o)=-0.031+/-0.002 in the film. These first results show the potential use of rf-sputtered NKN films as an electro-optical active material.
Place, publisher, year, edition, pages
2003. Vol. 82, no 3, 439-441 p.
Other Materials Engineering
IdentifiersURN: urn:nbn:se:kth:diva-22184DOI: 10.1063/1.1539295ISI: 000180449100043OAI: oai:DiVA.org:kth-22184DiVA: diva2:340882
QC 201005252010-08-102010-08-102010-09-28Bibliographically approved