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Static and dynamic properties of 0, pi, and 0-pi ferromagnetic tunnel Josephson Junctions

111   0   0.0 ( 0 )
 نشر من قبل Judith Pfeiffer
 تاريخ النشر 2008
  مجال البحث فيزياء
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We present experimental studies of static and dynamic properties of 0, pi and 0-pi superconductor-insulator-ferromagnet-superconductor (SIFS) Josephson junctions of small and intermediate length. In the underdamped limit these junctions exhibit a rich dynamical behavior such as resonant steps on the current-voltage characteristics. Varying the experimental conditions, zero field steps, Fiske steps and Shapiro steps are observed with a high resolution. A strong signature of the 0-pi Josephson junction is demonstrated by measuring the critical current as a function of two components (B_x, B_y) of an in-plane magnetic field. The experimental observation of a half-integer zero field step in 0-pi SIFS junctions is presented.

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