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Temperature stability of intersubband transitions in AlN/GaN quantum wells

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 نشر من قبل Kristian Berland
 تاريخ النشر 2010
  مجال البحث فيزياء
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Temperature dependence of intersubband transitions in AlN/GaN multiple quantum wells grown with molecular beam epitaxy is investigated both by absorption studies at different temperatures and modeling of conduction-band electrons. For the absorption study, the sample is heated in increments up to $400^circ$C. The self-consistent Schrodinger-Poisson modeling includes temperature effects of the band-gap and the influence of thermal expansion on the piezoelectric field. We find that the intersubband absorption energy decreases only by $sim 6$ meV at $400^circ$C relative to its room temperature value.



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