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Non-Local Correlations in Normal Metal-Superconducting Systems

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 نشر من قبل Paul Cadden-Zimansky
 تاريخ النشر 2006
  مجال البحث فيزياء
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We examine nonlocal effects between normal-metal gold probes connected by superconducting aluminum. For highly transparent Au/Al interfaces, we find nonlocal voltages that obey a spatial and temperature evolution distinct from the nonequilibrium charge imbalance signals usually found in such systems. These voltages are consistent with the predicted effects of crossed Andreev reflection and elastic cotunneling, effects that involve coherent correlations between spatially separated electrons.



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