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Epitaxial growth and transport properties of Nb-doped SrTiO$_{3}$ thin films

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 نشر من قبل Kei Takahashi
 تاريخ النشر 2005
  مجال البحث فيزياء
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Nb-doped SrTiO$_{3}$ epitaxial thin films have been prepared on (001) SrTiO$_{3}$ substrates using pulsed laser deposition. A high substrate temperature ($>1000^{circ}{C}$) was found to be necessary to achieve 2-dimensional growth. Atomic force microscopy reveals atomically flat surfaces with 3.9 AA $ $ steps. The films show a metallic behavior, residual resistivity ratios between 10 and 100, and low residual resistivity of the order of 10$^{-4}$$Omega$cm. At 0.3 K, a sharp superconducting transition, reaching zero resistance, is observed.



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