Magnetoelectric effects in heavy-fermion superconductors without inversion symmetry

TL;DR

This paper explores how strong electron correlations influence magnetoelectric effects in noncentrosymmetric heavy-fermion superconductors, revealing that paramagnetic supercurrents remain unaffected by mass renormalization, making experimental detection more feasible.

Contribution

It provides a formally exact expression for the magnetoelectric coefficient considering electron correlations in heavy-fermion superconductors, highlighting the robustness of paramagnetic supercurrents.

Findings

Paramagnetic supercurrent is unaffected by Fermi liquid effects.

Magnetoelectric effect is more observable in heavy-fermion systems.

Contrasts with the reduced Meissner current in heavy-fermion states.

Abstract

We investigate effects of strong electron correlation on magnetoelectric transport phenomena in noncentrosymmetric superconductors with particular emphasis on its application to the recently discovered heavy-fermion superconductor CePt$_3$Si. Taking into account electron correlation effects in a formally exact way, we obtain the expression of the magnetoelectric coefficient for the Zeeman-field-induced paramagnetic supercurrent, of which the existence was predicted more than a decade ago. It is found that in contrast to the usual Meissner current, which is much reduced by the mass renormalization factor in the heavy-fermion state, the paramagnetic supercurrent is not affected by the Fermi liquid effect. This result implies that the experimental observation of the magnetoelectric effect is more feasible in heavy-fermion systems than that in conventional metals with moderate effective mass.