Mid-infrared conductivity from mid-gap states associated with charge stripes

  title={Mid-infrared conductivity from mid-gap states associated with charge stripes},
  author={Christopher C. Homes and John M. Tranquada and Q. Li and Arnie. R. Moodenbaugh and Douglas J. Buttrey},
  journal={Physical Review B},
15 , a material in which the charge stripes order three dimensionally. We show that the conductivity can be decomposed into two components, a mid-infrared peak that we attribute to transitions from the filled valence band into empty mid-gap states associated with the stripes, and a Drude peak that appears at higher temperatures as carriers are thermally excited into the mid-gap states. The shift of the mid-IR peak to lower energy with increasing temperature is explained in terms of the Franck… 

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