Authors: T. Tätte, M. Paalo, M. Part, V. Kisand, A. Lõhmus, I. Kink
Affilation: University of Tartu, Estonia
Pages: 109 - 111
Keywords: sol-gel, nano optics, nanostructures, nanofibres
Recently many nanoscale silica structures have been suggested for optics device design. For example silica nanoneedles are used for focusing light into spot some tens of nanometers in diameter and sub-wavelength diameter silica fibres are proposed for sensor applications. However, there are insuperable drawbacks in realizing devises based on silica (glass and quartz) because of their low refractive indexes. To overcome these drawbacks high refractive index materials like transition metal oxides must be used instead of silica. In order to shape transition metal oxides to low-dimensional fibers and needles we have recently proposed a new approach that utilizes alkoxide based concentrates as precursors. The precursors are suitable for pulling nanometrically sharp needles, nanofibers and can be effectively used for grafting defined shape microscopic oxide lines to different flat substrates. Technology suitable for connecting separate points on flat surfaces with oxide fibres is suggested. Being carried out at room temperature, technologies based on concentrates have advantages like easier doping and possibility to structure substrates that decompose at elevated temperatures. In this work we generalize the conceptual background of preparation of transition metal oxides, and describe the critical aspects related to its use in real production.