Study of luminescence and optical resonances in Sb_2O_3 micro- and nanotriangles

© Springer Science+Business Media Dordrecht 2012. Acknowledgments This work has been supported by Spanish MICINN through projects MAT 2009-07882 and Consolider 2010-00013.
Luminescence of micro-and nanotriangles of cubic antimony oxide, Sb_2O_3 has been investigated by cathodoluminescence (CL) in scanning electron microscope and by photoluminescence (PL) in a laser confocal microscope. The triangles were grown by a thermal evaporation-deposition process with pure antimony powders as precursor, and present a self assembled arrangement covering extended areas of the samples. CL spectra of the triangles show bands at 2-2.5 and 3.1 eV, the latter is not observed in the Sb_2O_3 initial powder. PL excited by 325 nm laser shows a band at 2.4 eV with a shoulder at 2.75 eV, as well as resonance modes suggesting optical cavity behavior of the triangles. The separation between resonant peaks from different triangles has been correlated with the triangle side length and possible optical paths were obtained according to the Fabry-Perot relationship. These results along with the optical images suggest that not only Fabry-Perot cavity modes, but also whispering gallery modes may occur inside the micro-and nanotriangle structures.
Spanish MICINN
Depto. de Física de Materiales
Fac. de Ciencias Físicas
TRUE
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