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Mesoscopic electronic heterogeneities in the transport properties of V2O3 thin films

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 نشر من قبل Alain Pautrat
 تاريخ النشر 2008
  مجال البحث فيزياء
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The spectacular metal-to-insulator transition of V2O3 can be progressively suppressed in thin film samples. Evidence for phase separation was observed using microbridges as a mesoscopic probe of transport properties where the same film possesses domains that exhibit a metal-to-insulator transition with clear first order features or remain metallic down to low temperatures. A simple model consisting of two parallel resistors can be used to quantify a phase coexistence scenario explaining the measured macroscopic transport properties. The interaction between film and substrate is the most plausible candidate to explain this extended phase coexistence as shown by a correlation between the transport properties and the structural data.



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