Manipulation of time reversal symmetry breaking superconductivity in Sr<sub>2</sub>RuO<sub>4</sub> by uniaxial strain
· Invited
Abstract
Although the normal-state electronic structure of Sr2RuO4 is known with exceptional precision, even after two decades of research, the symmetry of it’s certainly unconventional superconducting state is currently under strong debate, e.g. the long time favoured spin-triplet px + i py state is ruled out by recent NMR experiments [1]. However, in general time-reversal-symmetry breaking (TRSB) superconductivity indicates complex two-component order parameters. Probing Sr2RuO4 under uniaxial offers the possibility to lift the degeneracy between such components [2]. One key prediction for Sr2RuO4, a splitting of the superconducting and TRSB transitions under uniaxial stress has not been observed so far.
Here, we report results of muon spin relaxation (μSR) measurements on Sr2RuO4 placed under uniaxial stress. We observed a large stress-induced splitting between the onset temperatures of superconductivity and TRSB. Moreover, at high stress beyond the van Hove singularity [2], the TRSB phase is suppressed and a long-range ordered magnetic spin density wave phase is observed with an approx. 50 times stronger internal field.
We will discuss the uniaxial strain dependent electronic phase diagram and its implications for the symmetry of the superconducting order parameter in Sr2RuO4.
[1] A. Pustogow, et al., arXiv:1904.00047; K. Ishida et al., arXiv:1907.12236.
[2] C. Hicks, et al., Science 344, 283 (2014), M. E. Barber, et al., Phys. Rev. Lett. 120, 076602 (2018).
Here, we report results of muon spin relaxation (μSR) measurements on Sr2RuO4 placed under uniaxial stress. We observed a large stress-induced splitting between the onset temperatures of superconductivity and TRSB. Moreover, at high stress beyond the van Hove singularity [2], the TRSB phase is suppressed and a long-range ordered magnetic spin density wave phase is observed with an approx. 50 times stronger internal field.
We will discuss the uniaxial strain dependent electronic phase diagram and its implications for the symmetry of the superconducting order parameter in Sr2RuO4.
[1] A. Pustogow, et al., arXiv:1904.00047; K. Ishida et al., arXiv:1907.12236.
[2] C. Hicks, et al., Science 344, 283 (2014), M. E. Barber, et al., Phys. Rev. Lett. 120, 076602 (2018).
*This work was supported by DFG (GR 4667, GRK 1621, and SFB 1143).
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Presenters
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Hans-Henning Klauss
- Faculty of Physics, TU Dresden, Germany
- Institute for Solid State and Materials Physics,Technical University of Dresden, Germany