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Problem: Excitons

      Excitons are bound electron-hole pairs, typically observed in semiconductors. Assume that the conduction and valence bands are described by

equation2012

with m being the free-electron mass and tex2html_wrap_inline6309 eV. Estimate the binding energy of an exciton, assuming a dielectric constant of tex2html_wrap_inline6311 . At what temperatures could we observe excitons?

 

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Laszlo Mihaly
Thu Oct 31 13:23:11 EST 1996

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