[20p-B204-1~13] 6.3 Oxide electronics

△ [20p-B204-2] Superconductivity in pseudo-rocksalt structure Nb₃O₃ epitaxial thin films

〇(M1)Rintaro Kimura¹, Yasumichi Cho¹, Kenichi Kaminaga¹, Shingo Maruyama¹, Yuji Matsumoto¹ (1.Tohoku Grad. Sch.)

Keywords:Pulsed Laser Deposition, Superconductivity, Niobium Oxide

Niobium monoxide (NbO) has a pseudo-rocksalt structure (Nb₃O₃, a = 4.21 Å) with each of Nb and O equally missing by 25% from the rock-salt structure (Nb₄O₄) and shows metallic superconductivity at T_c = 1.5 K. NbO was reported only as a pseudo-rocksalt structure in bulk, but not as a thin film. Previously, we discussed the possibility that the rock-salt Nb₄O₄ thin film fabricated by PLD method is a high mobility Mott insulator. In this study, we have also succeeded in fabricating pseudo-rocksalt Nb₃O₃ epitaxial thin films by adjusting the film formation conditions, and observed superconductivity at T_c^onset = 3.5 K, which is higher than that of the bulk material.