Jc control of $Nb/A1_2O_3/Nb$ Josephson junction

$Nb/A1_2O_3/Nb$ 조셉슨 접합의 임계전류밀도 제어

  • 김규태 (한국표준과학연구원 전기자기그룹) ;
  • 홍현권 (충북대 대학원 전자공학과) ;
  • 이규원 (한국표준과학연구원 초전도그룹 책임연구원)
  • Published : 2002.05.01

Abstract

Single Josephson junctions, which are of cross type, of $50 ${\mu}{\textrm}{m}$ {\times} 50 ${\mu}{\textrm}{m}$$ were fabricated under several oxidation conditions to Investigate controllabilities of critical current density (Jc) with the standard KRISS processes. Considering that the self-field effect suppresses the observed critical current (Ice) at high Jc region, we could reasonably estimate Jc values from I-V observations. The dependence of the obtained Jc as a function of exposure, which is equal to pressure (P) times time (t), was well fitted to a curve of Jc ~ (Pt)-0.34. The maximum Jc value at the controllability margin was found to be 3 kA/cm$^2$with the current equipment set up.

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References

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