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Kondo resonance enhanced supercurrent in single wall carbon nanotube Josephson junctions

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 نشر من قبل Kasper Grove-Rasmussen
 تاريخ النشر 2006
  مجال البحث فيزياء
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We have contacted single wall carbon nanotubes grown by chemical vapor deposition to superconducting Ti/Al/Ti electrodes. The device, we here report on is in the Kondo regime exhibiting a four-fold shell structure, where a clear signature of the superconducting electrodes is observed below the critical temperature. Multiple Andreev reflections are revealed by sub-gap structure and a narrow peak in the differential conductance around zero bias is seen depending on the shell filling. We interpret the peak as a proximity induced supercurrent and examine its interplay with Kondo resonances.



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