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arXiv · 1010.5892

π junction transition in InAs self-assembled quantum dot coupled with SQUID

S. Kim·R. Ishiguro·M. Kamio·Y. Doda·E. Watanebe·K. Shibata·K. Hirakawa·H. Takayanagi
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Abstract

We report the transport measurements on the InAs self-assembled quantum dots (SAQDs) which have a unique structural zero-dimensionality, coupled to a superconducting quantum interference device (SQUID). Owing to the SQUID geometry, we directly observe a π phase shift in the current phase relation and the negative supercurrent indicating π junction behavior by not only tuning the energy level of SAQD by back-gate but also controlling the coupling between SAQD and electrodes by side-gate. Our results inspire new future quantum information devices which can link optical, spin, and superconducting state.

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S. Kim, R. Ishiguro, M. Kamio, Y. Doda, E. Watanebe, K. Shibata, K. Hirakawa, H. Takayanagi. 2010-10-28. π junction transition in InAs self-assembled quantum dot coupled with SQUID. https://doi.org/10.1063/1.3552715

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