Abstract
Photonic crystals based on anodic aluminum oxide films are examined as refractive index sensors for controlling the composition of water-alcohol liquid mixtures. The position of the reflectance maximum corresponding to the first photonic stop band is used as the analytical signal. Impregnation of a photonic crystal with water-ethanol and water-glycerol mixtures results in a redshift of the reflectance maximum. A fairly high refractive index sensitivity, sufficient to determine the composition of water-ethanol and water-glycerol mixtures with an accuracy of about 1 wt.%, is observed. The detailed dependencies of the analytical signal on the composition of mixtures are experimentally investigated and compared with numerical calculations. Prospects and limitations of the refractive index sensors based on anodic alumina photonic crystals are discussed.
Highlights
A visually-recognizable chemical sensing or bio-sensing is a promising application of photonic crystals (PCs) [1,2,3]
Photonic crystals based on anodic aluminum oxide films demonstrate clear stop band shift with the impregnation by different liquids
The corresponding data for full width at half maximum (FWHM) of the peak are shown in is the effective refractive index of the porous structure, ni is a refractive index of the media inside the pores, nAO = 1.76 is the refractive index of aluminum oxide, and P is the porosity averaged over alternating layers
Summary
A visually-recognizable chemical sensing or bio-sensing is a promising application of photonic crystals (PCs) [1,2,3]. The analytical signal may be caused by changing the effective refractive index [4,5,6,7,8,9,10,11] and the diffracting-plane spacing [12,13,14,15] (see in [2]) or both the parameters simultaneously [16, 17] under the influence of certain analytes. Much attention has been devoted to sensors based on anodic aluminum oxide (AAO) one-dimensional PCs [18]. The refractive index of aluminum oxide, nAO ≈1.76, is high enough to work with impregnating liquids without fear of coincidence of the refractive indices and the Photonic Sensors associated loss of the analytical signal (such situation was considered in [30] for SiO2 PCs)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
