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arXiv · 2308.14892

Perturbation theory analysis of the strain-dependent superconducting phase diagram for Sr$_2$RuO$_4$

John Deisz
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Abstract

Previously, it was shown that a superconducting state dominated by singlet $d_{x^2-y^2}$ intra-band pairs emerges from the fluctuation exchange approximation (FLEX) applied to a realistic model for Sr$_2$RuO$_4$, a result that is increasingly in alignment with experimental data. Here we apply FLEX to model the strain-dependent phase diagram of Sr$_2$RuO$_4$ and show that we are able to reproduce its unusual features. This adds weight to the argument that a predominantly $d_{x^2-y^2}$ singlet pairing state represents a reasonable starting point for describing the superconducting properties of Sr$_2$RuO$_4$.

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John Deisz. 2023-08-28. Perturbation theory analysis of the strain-dependent superconducting phase diagram for Sr$_2$RuO$_4$. https://arxiv.org/abs/2308.14892

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