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Fabrication and Characterization of Superconducting Quantum Interference Device using (Bi_{1-x}Sb_x)_2Se_3 Topological Insulator Nanoribbons

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 نشر من قبل Yong-Joo Doh
 تاريخ النشر 2018
  مجال البحث فيزياء
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We report on the fabrication and electrical transport properties of superconducting quantum interference devices (SQUIDs) made from a (Bi_{1-x}Sb_x)_2Se_3 topological insulator (TI) nanoribbon (NR) connected with Pb0.5In0.5 superconducting electrodes. Below the transition temperature of the superconducting Pb0.5In0.5 electrodes, periodic oscillations of the critical current are observed in the TI NR SQUID under a magnetic field applied perpendicular to the plane owing to flux quantization. Also the output voltage modulates as a function of the external magnetic field. Moreover, the SQUID the SQUID shows a voltage modulation envelope, which is considered to represent the Fraunhofer-like patterns of each single junction. These properties of the TI NR SQUID would provide a useful method to explore Majorana fermions.



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