Photo of Richard K. Ahrenkiel

Richard K. Ahrenkiel

  • Metallurgical and Materials Engineering
  • Colorado School of Mines
    Golden, CO 80401


  • Education and Training.
  • PhD in Solid State Physics, University of Illinois
  • M.S. in Physics, University of Illinois
  • B.S. in Engineering Physics, University of Illinois
  • Honors and Awards
  • Fellow of the American Physical Society,
  • Life Fellow of the IEEE,
  • Fellow of the American Vacuum Society,
  • Fellow of the Optical Society of America,
  • Hubbard Award Winner for Contributions to Photovoltaics (1998).


  • Carrier Lifetime: Measurement and Theory
  • Photovoltaic Device Theory and Measurement.
  • Microelectronic Devices and Structures.
  • Thermoelectric device design and theory.
  • Defect Analysis: deep level transient spectroscopy.
  • Photoluminescence Analysis; measurement and theory.
  • Current-voltage (I-V) analysis of devices; measurement and theory.
  • Light emitting devices: semiconductor lasers and LEDs.
  • Solid state amplifiers/MOSFETs, JFETS, MesFETS.
  • Surface passivation of silicon and compound semiconducting materials: techniques and analysis.


  • Research Fellow Emeritus: National Renewable Energy Laboratory.
  • Prof. Adjunct: Department of Electrical, Computer, and Energy Engineering,Univ. of Colorado, Boulder, CO.
  • Short course instructor: American Vacuum Society.
  • Consultant to private industry.
  • Chief Technical Officer: Lakewood Semiconductors.


  • J. Moseley, M.M. Al-Jassim, H.R. Moutinho, H.L. Guthrey, W.K. Metzger, R.K. Ahrenkiel, Explanation of red spectral shifts at CdTe grain boundaries, Applied Physics Letters (2013, in press).
  • R. Bergen, B. J. Simonds, B. Yan, G. Yue, R. K. Ahrenkiel, T. E. Furtak, R. T. Collins, P. C. Taylor, and M. C. Beard, Electron transfer in hydrogenated nanocrystalline silicon observed by time-resolved terahertz spectroscopy, Phys. Rev. B 87, 081301(R) (2013).
  • Richard K Ahrenkiel, Resonant Coupling For Contactless Measurement of Carrier Lifetime, J. Vac. Sci. Technol. B 31, 04D113 - 04D113-8 (2013).
  • Darius Kuciauskas, Ana Kanevce, Joel N. Duenow, Ramesh Dhere, David S. Albin, Dean H. Levi, and Richard K. Ahrenkiel, Minority Carrier Lifetime Analysis in the Bulk of Thin Film Absorbers Using Sub-bandgap (Two-Photon) Excitation, IEEE Journal of Photovoltaics 3, 1319-1324 (2013).
  • Ari Feldman, Richard Ahrenkiel, and John Lehman, Degradation of Photovoltaic Devices at High Concentration by Space Charge Limited Currents, Solar Energy Materials and Solar Cells 117, pp. 408411 (2013).
  • Ari Feldman, Richard Ahrenkiel, and John Lehman, Transient mobility in silicon as seen by a combination of free-carrier absorption and resonance-coupled photoconductive decay, J. Appl. Phys. 112, 103703 (2013).
  • R. K. Ahrenkiel, A. Feldman, J. Lehman, and S. W. Johnston, Novel Free-Carrier Pump-Probe Analysis of Carrier Transport in Semiconductors, IEEE Journal of Photovoltaics 3. Pp. 348-352 (2013).
  • R. K. Ahrenkiel and D. J. Dunlavy, A new lifetime diagnostic system for photovoltaic materials, Solar Energy Materials and Solar Cells, 95 (2011), 1985-1989.
  • R.K. Ahrenkiel, N. Call, S.W. Johnston, W.K. Metzger, Comparison of techniques for measuring carrier lifetime in thin-film and multicrystalline photovoltaic materials, Solar Energy Materials and Solar Cells 95 (2010), 2197-2204.