SCIENCE AT THE EDGE SEMINAR SERIES

Interdisciplinary Physics Seminar

Friday, 06 April 2012 at 11:30am

Room 1400 Biomedical and Physical Sciences Bldg.

Refreshments at 11:15

Speaker: Victor Karpov
         Department of Physics and Astronomy
         University of Toledo

Title:   Physics of Thin Film Photovoltaics

Abstract:

Thin film photovoltaics (PV), particularly based on CdTe and CIGS absorbers,
are rapidly taking over world energy markets.  But do we understand their
operations?  Is that the same old concept of illuminated p-n junction making
it from one textbook to another or is there some new physics behind their
success?

As an introduction, I will give a brief 'first hand' account of a history of
the First Solar LLC, the company that started thin film PV to become a world
leader: its product, evolution, and current problems.

The topic of physics per se will start with a short review of the mainstream
understanding of classical photovoltaics (crystalline Si, etc.), showing that
it is absolutely insufficient to understand thin film photovoltaics and yet is
blindly applied.  I will then introduce several qualitatively different concepts
based on the experimental observations that form a new physics of thin-film PV.
They include the concept of random diode arrays, piezo-photovoltaic coupling,
and reach-through interactions.

My talk will include some practical implications, particularly the "red wine
effect" highlighted in the media. At the end, I will try to convey the message
that physicists owe a lot to the fascinating field of thin film PV that keeps
evolving by trial and error.