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arXiv · 2501.03591

Metallisation of the Mott Insulator Ca$_{2}$RuO$_{4}$ using Electric Double-Layer Gating

Tatsuhiro Sakami·Hiroki Ogura·Akihiro Ino·Takumi Ouchi·Tsutomu Nojima·Fumihiko Nakamura
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Abstract

To verify whether the Mott insulator Ca2RuO4 can be switched by applying electric-field alone, regardless of current flow, we employ metallisation using electric double-layer gating (EDLG). The resistance change due to EDLG occurs only when positive gate-voltage above +3 V is applied. The amplitude of the reduction, reaching ~97% of the initial value, is difficult to interpret as surface metallisation and is likely related to structural change in bulk.

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Tatsuhiro Sakami, Hiroki Ogura, Akihiro Ino, Takumi Ouchi, Tsutomu Nojima, Fumihiko Nakamura. 2025-01-07. Metallisation of the Mott Insulator Ca$_{2}$RuO$_{4}$ using Electric Double-Layer Gating. https://doi.org/10.7566/jpsj.94.023703

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