A Chiral Triplet Quasi-Two-Dimensional Superconductor in a Parallel Magnetic Field

TL;DR

This paper calculates the upper critical magnetic field for a chiral triplet superconductor in a quasi-two-dimensional system at zero temperature, revealing a discrepancy with experimental data in Sr₂RuO₄ that challenges the chiral triplet superconductivity hypothesis.

Contribution

The study provides a theoretical calculation of the critical magnetic field ratio in Q2D chiral triplet superconductors, offering evidence against the chiral triplet scenario in Sr₂RuO₄.

Findings

Calculated critical field ratio 0.815 at T=0.

Discrepancy with experimental data in Sr₂RuO₄.

Supports questioning of chiral triplet pairing in Sr₂RuO₄.

Abstract

We calculate the parallel upper critical magnetic field $H_{\parallel}(0)$ for an in-plane isotropic quasi-two-dimensional (Q2D) chiral triplet superconductor at zero temperature, $T=0$. In particular, the ratio $H_{\parallel}(0)/(|dH^{GL}_{\parallel}/dT|_{T=T_c}T_c) = 0.815$ is defined, where $|dH^{GL}_{\parallel}/dT|_{T=T_c}$ is the so-called Ginzburg-Landau slope of the upper critical magnetic field, $T_c$ is a superconducting transition temperature at $H=0$. We show that the theoretically obtained above mentioned value strongly contradicts to the experimentally measured ones in a candidate for a chiral triplet superconductivity Sr$_2$RuO$_4$, which provides one more argument against the chiral triplet scenario of superconductivity in this compound. Our results may be useful for establishing chiral triplet superconductivity in other Q2D candidates for this phenomenon.