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DOE OSTI · 1617236

Electronic nematicity in Sr 2 RuO 4

Wu, Jie·Nair, Hari P.·Bollinger, Anthony T.·He, Xi·Robinson, Ian·Schreiber, Nathaniel J.·Shen, Kyle M.·Schlom, Darrell G.·Božović, Ivan (ORCID:0000000164007461)
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Abstract

We have measured the angle-resolved transverse resistivity (ARTR), a sensitive indicator of electronic anisotropy, in high-quality thin films of the unconventional superconductor Sr 2 RuO 4 grown on various substrates. The ARTR signal, heralding the electronic nematicity or a large nematic susceptibility, is present and substantial already at room temperature and grows by an order of magnitude upon cooling down to 4 K. In Sr 2 RuO 4 films deposited on tetragonal substrates the highest-conductivity direction does not coincide with any crystallographic axis. In films deposited on orthorhombic substrates it tends to align with the shorter axis; however, the magnitude of the anisotropy stays the same despite the large lattice distortion. These are strong indications of actual or incipient electronic nematicity in Sr 2 RuO 4 .

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75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYangle-resolved transverse resistivityelectronic nematicitymolecular-beam epitaxystrontium ruthenate

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Wu, Jie, Nair, Hari P., Bollinger, Anthony T., He, Xi, Robinson, Ian, Schreiber, Nathaniel J., Shen, Kyle M., Schlom, Darrell G., Božović, Ivan (ORCID:0000000164007461). 2020-05-04. Electronic nematicity in Sr 2 RuO 4. https://doi.org/10.1073/pnas.1921713117

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