Nanoliter liquid characterization by open whispering-gallery mode dielectric resonators at millimeter wave frequencies

We present an approach for identification and concentration determination of liquids of pico to nanoliter volumes at a frequency of 35 GHz based on a whispering-gallery mode (WGM) dielectric resonator technique. A quasioptical coupling scheme based on dielectric image waveguides was employed to exci...

Full description

Saved in:
Bibliographic Details
Published in:Journal of applied physics 2008-10, Vol.104 (7), p.074111-074111-7
Main Authors: Shaforost, E. N., Klein, N., Vitusevich, S. A., Offenhäusser, A., Barannik, A. A.
Format: Article
Language:English
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We present an approach for identification and concentration determination of liquids of pico to nanoliter volumes at a frequency of 35 GHz based on a whispering-gallery mode (WGM) dielectric resonator technique. A quasioptical coupling scheme based on dielectric image waveguides was employed to excite high- Q running wave WGMs with uniform azimuthal field distribution in cylindrical sapphire disks with quality factors up to 4 × 10 5 at room temperature. Measurement of the liquid induced changes in the resonator quality factor and resonance frequency has been performed for droplets down to 90 pl volume spotted at different positions on the surface of the sapphire disk. We have employed our method for concentration determination of ethanol, glucose, and albumin dissolved in water. Solutions with concentration values well below 10% could be clearly separated from pure water. Our method is promising for the characterization of biological liquids.
ISSN:0021-8979
1089-7550
DOI:10.1063/1.2991182