Shawn-Yu Lin, Rensselaer Polytechnic Institute, Troy, New York, and co-workers have doubled the current standard of detectivity for quantum dot-based infrared photodetectors (QDIP) and expect to be able to further enhance it by up to 20 times.

The solid surface of the structure that Lin et al. built is covered with about 50 nm of gold and pitted with holes, about 1.6 µm in diameter, and 1 µm deep. The nanoscopic gold focuses the light entering the infrared detector, which in turn enhances the absorption of photons and the capacity of the embedded quantum dots to convert the photons into electrons.

“More effective infrared satellite imaging technology holds the potential to benefit everything from homeland security to monitoring climate change and deforestation,” said Lin.

• A Surface Plasmon Enhanced Infrared Photodetector Based on InAs Quantum Dots
  C.-C. Chang, Y. Sharma, Y.-S. Kim, J. Bur, R. Shenoi, S. Krishna, D. Huang, S.-Y. Lin, Nano Lett. 2010, 10, 1704–1709.
  DOI: 10.1021/nl100081j