Research

My research activities are concerned with characterization of fundamental loss mechanisms in solar cells and electronic properties of semiconductors and organic materials used for applications in solar cells. Lately, I have started to also conduct research on photon upconversion for 3rd generation photovoltaics. My working groups runs an EPR facility together with the Free University Berlin, the so-called Joint Berlin EPR Laboratory (BeJEL). At BeJEL we try to identify the performance limiting defects of solar cell materials. The main methods that we use for such studies are

  • Continuous-wave electron paramagnetic resonance (cw EPR) and time-domain EPR
  • Electrically and optically detected magnetic resonance (EDMR and ODMR)
    Detection in both continuous-wave and time-domain
  • Photoluminescence
  • Hall effect
  • Scanning electron microscopy
  • Synchrotron-based methods such as THz-EPR and HAXPES

Since 2011 I am the leading manager of the EMIL project at HZB, which is a unique laboratory dedicated to solar cell preparation and in-situ/in-system characterization using X-ray spectroscopy. EMIL will be directly placed at the BESSY II light source and will operate a dedicated X-ray beamline in the energy range 80 eV - 10 keV. EMIL will be taken into operation in 2015.