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Snells law for surface electrons: Refraction of an electron gas imaged in real space

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 نشر من قبل Jascha Repp
 تاريخ النشر 2003
  مجال البحث فيزياء
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On NaCl(100)/Cu(111) an interface state band is observed that descends from the surface-state band of the clean copper surface. This band exhibits a Moire-pattern-induced one-dimensional band gap, which is accompanied by strong standing-wave patterns, as revealed in low-temperature scanning tunneling microscopy images. At NaCl island step edges, one can directly see the refraction of these standing waves, which obey Snells refraction law.



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