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arXiv · 2505.14997

Superconducting vacancy-ordered rock-salt NbO films

Jeong Rae Kim·Sandra Glotzer·Evan Krysko·Matthew R. Barone·Jinkwon Kim·Salva Salmani-Rezaie·Adrian Llanos·Joseph Falson
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Abstract

We report molecular beam epitaxy synthesis of vacancy-ordered rocksalt NbO thin films which display superconductivity. A comparative study of substrates identifies Al$_2$O$_3$ (0001) as the optimal platform for realizing high-quality, single-phase films when growing at temperatures exceeding 1000 $^\circ$C. The controlled NbO films exhibit superconductivity with critical temperatures up to $T_\mathrm{c}$ = 1.37 K, comparable to bulk single crystals. This work addresses the fundamental bottlenecks encountered in the high-temperature epitaxy of compounds with uncommon oxidation states, while expanding the scope of available thin-film superconductors.

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Jeong Rae Kim, Sandra Glotzer, Evan Krysko, Matthew R. Barone, Jinkwon Kim, Salva Salmani-Rezaie, Adrian Llanos, Joseph Falson. 2025-05-21. Superconducting vacancy-ordered rock-salt NbO films. https://arxiv.org/abs/2505.14997

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