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DOE OSTI · 3366215

Strain-induced superconductivity in RuO 2 (100) thin-films

Wadehra, Neha [Cornell University, Ithaca, NY (United States)] (ORCID:000000017375862X)·Gregory, Benjamin Z. [Cornell University, Ithaca, NY (United States)]·Zhang, Shuyuan [Cornell University, Ithaca, NY (United States)]·Schnitzer, Noah [Cornell University, Ithaca, NY (United States)]·Iguchi, Yusuke [Stanford University, CA (United States); SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)]·Li, Yilin Evan [Cornell University, Ithaca, NY (United States)] (ORCID:0000000166891406)·Pamuk, Betül [Cornell University, Ithaca, NY (United States); Cornell University, New York, NY (United States); Williams College, Williamstown, MA (United States)]·Muller, David A. [Cornell University, Ithaca, NY (United States); Cornell University, New York, NY (United States)] (ORCID:0000000341290473)·Singer, Andrej [Cornell University, Ithaca, NY (United States)] (ORCID:0000000229659242)·Shen, Kyle M. [Cornell University, Ithaca, NY (United States)] (ORCID:0000000169763434)·Schlom, Darrell G. [Cornell University, Ithaca, NY (United States); Leibniz-Institut für Kristallzüchtung, Berlin (Germany)] (ORCID:0000000324936113)
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Abstract

Recently, superconductivity was discovered with a superconducting transition temperature (T c ) of 2 K in strained (110)-oriented RuO 2 films grown on TiO 2 (110) single-crystal substrates. In this work, we predict and realize superconductivity in strained (100)-oriented RuO 2 thin films grown on TiO 2 (100) single-crystal substrates. We show that while density functional theory predicts the T c of strained RuO 2 (100) films to be even higher than the RuO 2 (110) films, our transport and angle-resolved photoemission spectroscopy measurements find the T c to be about 1 K in strained RuO 2 (100) films grown on TiO 2 (100) substrates. Nonetheless, the thickness dependence of the T c follows a similar trend in both cases. Our scanning SQUID measurements reveal a local superfluid response, indicating a 100 mK inhomogeneity in T c over a 100 μm scale.

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Wadehra, Neha [Cornell University, Ithaca, NY (United States)] (ORCID:000000017375862X), Gregory, Benjamin Z. [Cornell University, Ithaca, NY (United States)], Zhang, Shuyuan [Cornell University, Ithaca, NY (United States)], Schnitzer, Noah [Cornell University, Ithaca, NY (United States)], Iguchi, Yusuke [Stanford University, CA (United States); SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)], Li, Yilin Evan [Cornell University, Ithaca, NY (United States)] (ORCID:0000000166891406), Pamuk, Betül [Cornell University, Ithaca, NY (United States); Cornell University, New York, NY (United States); Williams College, Williamstown, MA (United States)], Muller, David A. [Cornell University, Ithaca, NY (United States); Cornell University, New York, NY (United States)] (ORCID:0000000341290473), Singer, Andrej [Cornell University, Ithaca, NY (United States)] (ORCID:0000000229659242), Shen, Kyle M. [Cornell University, Ithaca, NY (United States)] (ORCID:0000000169763434), Schlom, Darrell G. [Cornell University, Ithaca, NY (United States); Leibniz-Institut für Kristallzüchtung, Berlin (Germany)] (ORCID:0000000324936113). 2025-07-03. Strain-induced superconductivity in RuO 2 (100) thin-films. https://doi.org/10.1038/s43246-025-00856-6

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