Microwave-to-terahertz dielectric resonators for liquid sensing in microfluidic systems

Research output: Chapter in Book/Report/Conference proceedingConference contribution


  • N. Klein
  • C. Watts
  • W. J. Otter
  • M. M. Ahmad
  • S. Lucyszyn

Colleges, School and Institutes

External organisations

  • Imperial College London
  • Department of Materials


The microwave-to-terahertz frequency range offers unique opportunities for the sensing of liquids based on the degree of molecular orientational and electronic polarization, Debye relaxation due to intermolecular forces between (semi-)polar molecules and collective vibrational modes within complex molecules. Methods for the fast dielectric characterization of (sub-)nanolitre volumes of mostly aqueous liquids and biological cell suspensions are discussed, with emphasis on labon-chip approaches aimed towards single-cell detection and label-free flow cytometry at microwave-to-terahertz frequencies. Among the most promising approaches, photonic crystal defect cavities made from high-resistivity silicon are compared with metallic split-ring resonant systems and high quality factor (Q-factor) whispering gallery-type resonances in dielectric resonators. Applications range from accurate haemoglobin measurements on nanolitre samples to label-free detection of circulating tumor cells.


Original languageEnglish
Title of host publicationTerahertz Emitters, Receivers, and Applications VII
EditorsManijeh Razeghi, Alexei N. Baranov, John M. Zavada, Dimitris Pavlidis
Publication statusPublished - 26 Sep 2016
EventTerahertz Emitters, Receivers, and Applications VII - San Diego, United States
Duration: 28 Aug 201631 Aug 2016

Publication series

NameProceedings of SPIE - The International Society for Optical Engineering
ISSN (Print)0277-786X
ISSN (Electronic)1996-756X


ConferenceTerahertz Emitters, Receivers, and Applications VII
CountryUnited States
CitySan Diego


  • dielectric resonators, label free cancer cell detection, microwave and terahertz liquid characterization, photonic crystal resonators

Sustainable Development Goals