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Mutually synchronized macroscopic Josephson oscillations demonstrated by polarization analysis of superconducting terahertz emitters

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 نشر من قبل Manabu Tsujimoto
 تاريخ النشر 2020
  مجال البحث فيزياء
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We demonstrate mutual synchronization of Josephson oscillations in multiple stacks of intrinsic Josephson junctions of the cuprate superconductor Bi$_2$Sr$_2$CaCu$_2$O$_{8+delta }$. Detailed analysis of the full polarization parameters allows the determination of a phase correlation between the stacks: a simultaneous emission state is described by a linear combination of individual emission states with a phase retardation. This proves that the stacks are coupled via a Josephson plasma in a superconducting substrate and the coupling matrices can be extracted from polarization analyses. Our findings suggest a route towards the realization of high-power terahertz sources based on the synchronization of a large number of intrinsic Josephson junctions.



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