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arXiv · 1306.5033

Probing active/passive bands by quasiparticle interference in Sr$_{2}$RuO$_{4}$

Yi Gao·Tao Zhou·Huaixiang Huang·C. S. Ting·Peiqing Tong·Qiang-Hua Wang
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Abstract

The quasiparticle interference (QPI) in Sr$_{2}$RuO$_{4}$ is theoretically studied based on two different pairing models in order to propose an experimental method to test them. For a recently proposed two-dimensional model with pairing primarily from the $\gamma$ band, we found clear QPI peaks evolving with energy and their locations can be determined from the tips of the constant-energy contour (CEC). On the other hand, for a former quasi-one-dimensional model with pairing on the $\alpha$ and $\beta$ bands, the QPI spectra are almost dispersionless and may involve off-shell contributions to the scatterings beyond the CEC. The different behaviors of the QPI in these two models may help to resolve the controversy of active/passive bands and whether Sr$_{2}$RuO$_{4}$ is a topological superconductor.

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Yi Gao, Tao Zhou, Huaixiang Huang, C. S. Ting, Peiqing Tong, Qiang-Hua Wang. 2013-06-21. Probing active/passive bands by quasiparticle interference in Sr$_{2}$RuO$_{4}$. https://doi.org/10.1103/physrevb.88.094514

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