Chemical contrast in soft x-ray ptychography

Phys Rev Lett. 2011 Nov 11;107(20):208101. doi: 10.1103/PhysRevLett.107.208101. Epub 2011 Nov 8.


The unique strengths of x-ray microscopy are high penetration depth and near-edge resonances that provide chemical information. We use ptychography, a coherent diffractive imaging technique that disposes of the requirement for isolated specimens, and demonstrate resonant imaging by exploiting resonances near the oxygen K edge to differentiate between two oxygen-containing materials. To highlight a biological system where resonant ptychography might be used for chemical mapping of unsliced cells, reconstructions of freeze-dried Deinococcus radiodurans cells at an energy of 517 eV are shown.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Deinococcus / cytology
  • Oxygen / chemistry
  • Polymethyl Methacrylate / chemistry
  • Silicon Dioxide / chemistry
  • X-Ray Diffraction / methods*


  • Silicon Dioxide
  • Polymethyl Methacrylate
  • Oxygen