1 MS JNP 17102P-R revised (oct 17 th , 2017) Vapor and Liquid Optical Monitoring with Sculptured Bragg Microcavities Manuel Oliva-Ramirez*, Jorge Gil-Rostra, Maria C. López-Santos, Agustín R. González- Elipe, Francisco Yubero * Instituto de Ciencia de Materiales de Sevilla (CSIC, University of Seville) , CICCartuja, Avda. Américo Vespucio 49, E-41092, Spain Abstract. Sculptured porous Bragg Microcavities (BMs) formed by the successive stacking of columnar SiO2 and TiO2 thin films with a zig-zag columnar microstructure are prepared by glancing angle deposition. These BMs act as wavelength dependent optical retarders. This optical behavior is attributed to a self-structuration of the stacked layers involving the lateral association of nanocolumns in the direction perpendicular to the main flux of particles during the multilayer film growth, as observed by Focused Ion Beam Scanning Electron Microscopy. The retardance of these optically active BMs can be modulated by dynamic infiltration of their open porosity with vapors, liquids or solutions with different refractive indices. The tunable birefringence of these nanostructured photonic systems have been successfully simulated with a simple model that assumes that each layer within the BMs stack has uniaxial birefringence. The sculptured BM have been incorporated as microfluidic chips for optical transduction for label free vapor and liquid