Nano sensor technology based on semiconductor nanocrystals


Martin J., Staudinger U., Demir E. , Spudat C., Poetschke P., Voit B., ...More

Conference on Integrated Optics - Devices, Materials, and Technologies XVI, San-Francisco, Costa Rica, 23 - 25 January 2012, vol.8264 identifier

  • Publication Type: Conference Paper / Full Text
  • Volume: 8264
  • Doi Number: 10.1117/12.922954
  • City: San-Francisco
  • Country: Costa Rica

Abstract

We present a new concept of material integrated sensor technology for detection, storage and visualization of mechanical stress and load conditions. Key feature is a double layer consisting of a piezoelectric layer and a semiconductor nanocrystal polymer composite film. Electrical charges are generated within the piezo layer by application of a mechanical load to the structure. The charges are transferred to the composite film and injected into the nanocrystals, causing non-radiative exciton recombination. This results in photoluminescence quenching, which can be detected as local optical contrast. The photoluminescence of CdSe/ZnS core/shell quantum dots has been switched off by application of external voltages smaller than 20 V. It was possible to store the charges in the QDs, and hence the off-state, for several hours. Optical contrast ratios up to 1: 125 have been detected so far.