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Electronic nematicity in Sr2RuO4.

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 Sr2RuO4 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 Sr2RuO4 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 Sr2RuO4.

SUBMITTER: Wu J

PROVIDER: S-EPMC7245092 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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Electronic nematicity in Sr2RuO4.

Wu Jie J Nair Hari P HP Bollinger Anthony T AT He Xi X Robinson Ian I Schreiber Nathaniel J NJ Shen Kyle M KM Schlom Darrell G DG Božović Ivan I

Proceedings of the National Academy of Sciences of the United States of America 20200504 20

We have measured the angle-resolved transverse resistivity (ARTR), a sensitive indicator of electronic anisotropy, in high-quality thin films of the unconventional superconductor Sr2RuO4 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 Sr2RuO4 films deposited on tetrag ...[more]

PMID: 32366660

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