Optical waveguiding in epitaxial Sr1.8Ca0.2NaNb 5O15 films integrated on Si(0 0 1) substrates

W. C. Liu, Chee Leung Mak, K. H. Wong

Research output: Journal article publicationJournal articleAcademic researchpeer-review

3 Citations (Scopus)


Epitaxial tetragonal tungsten-bronze structure Sr1.8Ca 0.2NaNb5O15 (SCNN) thin films of 650 nm thick have been grown on Si(0 0 1) substrates for the first time using pulsed laser deposition. The large lattice mismatch between SCNN films and Si substrates was overcome by making use of a MgO/TiN buffer layer. Excellent optical waveguiding properties of these SCNN films have been demonstrated using a prism-coupling technique. The ordinary and extraordinary refractive indices at 632.8 nm were calculated to be 2.2141 and 2.1727, respectively, implying a large birefringence of 0.0414. A propagation loss of 1.7 dB cm-1 was measured in our waveguides. Our studies suggest that the SCNN/MgO/TiN/Si heterostructure is an ideal candidate for integrated optical waveguide applications.
Original languageEnglish
Article number009
Pages (from-to)749-753
Number of pages5
JournalJournal of Physics D: Applied Physics
Issue number3
Publication statusPublished - 7 Feb 2007

ASJC Scopus subject areas

  • Physics and Astronomy (miscellaneous)

Cite this