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Superconductivity in quantum-dot superlattices composed of quantum wire networks

Takashi Kimura·Hiroyuki Tamura·Kazuhiko Kuroki·Kenji Shiraishi·Hideaki Takayanagi·Ryotaro Arita
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Abstract

Based on calculations using the local density approximation, we propose quantum wire networks with square and plaquette type lattice structures that form quantum dot superlattices. These artificial structures are well described by the Hubbard model. Numerical analysis reveals a superconducting ground state with transition temperatures $T_c$ of up to 90 mK for the plaquette, which is more than double the value of 40 mK for the square lattice type and is sufficiently high to allow for the experimental observation of superconductivity.

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Takashi Kimura, Hiroyuki Tamura, Kazuhiko Kuroki, Kenji Shiraishi, Hideaki Takayanagi, Ryotaro Arita. 2002-04-10. Superconductivity in quantum-dot superlattices composed of quantum wire networks. https://doi.org/10.1103/physrevb.66.132508

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