Deformation of the Fermi Surface and Anomalous Mass Renormalization by Critical Spin Fluctuations through Asymmetric Spin-Orbit Interaction

TL;DR

This paper investigates how critical spin fluctuations influence asymmetric spin-orbit interactions, such as Rashba, causing Fermi surface deformation and anomalous mass renormalization near magnetic quantum critical points.

Contribution

It predicts the renormalization effects of critical spin fluctuations on Rashba-type interactions and their impact on Fermi surface deformation and mass renormalization.

Findings

Anti-ferromagnetic fluctuations suppress Rashba interaction near hot spots.

Ferromagnetic fluctuations enhance Rashba interaction across the Fermi surface.

Mass renormalization diverges with opposite signs for split bands near criticality.

Abstract

It is shown that an asymmetric spin-orbit interaction is appreciably renormalized by the effect of critical spin fluctuations. As an explicit example, the Rashba-type interaction is predicted to be suppressed by anti-ferromagnetic critical fluctuations near the hot line (or point), leading to a deformation of the Fermi surface near the hot line (or point) around which the band splitting is decreased, while ferromagnetic critical fluctuations are shown to enhance the Rashba-type interaction everywhere on the Fermi surface, leading to an increase in the band splitting. It is also found that the many-body mass renormalization, which diverges towards the magnetic quantum critical point, is in the opposite sign for the two split bands by the Rashba-type interaction. These predictions are observable by the de Haas-van Alphen (dHvA) effect in principle.