Scattering on spin fluctuations in itinerant quantum disordered ferromagnets near quantum phase transition

TL;DR

This paper investigates how weak localization effects influence electron and neutron scattering on critical spin fluctuations near quantum phase transitions in disordered itinerant ferromagnets, revealing different scattering behaviors depending on electron density.

Contribution

It introduces a model accounting for long-range spin interactions due to weak localization effects and analyzes their impact on scattering near quantum critical points.

Findings

Electron transport cross section aligns with conventional critical fluctuations at low electron density.

Neutron scattering intensity diminishes exponentially with weak localization effects.

Multiple small-angle neutron scattering is significantly suppressed compared to conventional fluctuations.

Abstract

Taking into account the long-ranged spin interactions due to weak localization effects in disordered itinerant ferromagnets the scattering of both electrons and neutrons on critical spin fluctuations near quantum phase transition is considered. It is shown that for the case of low electron density, when k_F \xi \ll 1, where k_F is the Fermi momentum and \xi is the magnetic correlation length, the transport cross section of electrons is proportional to conventional critical fluctuations in absence of weak localization effects. However, the intensity of the multiple small-angle neutron scattering becomes exponentially small as compared with the intensity of the multiple scattering by conventional critical fluctuations.