Low-energy magnetic response of the noncentrosymmetric heavy-fermion superconductor CePt3Si studied via inelastic neutron scattering

TL;DR

This study investigates the magnetic excitations in the heavy-fermion superconductor CePt3Si using inelastic neutron scattering, revealing anisotropic spin fluctuations and their evolution across magnetic and superconducting transitions.

Contribution

It provides the first detailed measurement of low-energy magnetic excitations in CePt3Si, highlighting the anisotropic nature of spin fluctuations and their behavior through magnetic and superconducting phases.

Findings

Kondo-type spin fluctuations are observed in the paramagnetic state.

Spin fluctuations are replaced by damped spin waves below TN=2.2 K.

No change in magnetic excitations occurs across Tc=0.7 K.

Abstract

The low-energy magnetic excitations of the noncentrosymmetric heavy-fermion superconductor CePt3Si have been measured with inelastic neutron scattering on a single crystal. Kondo-type spin fluctuations with an anisotropic wave vector dependence are observed in the paramagnetic state. These fluctuations do not survive in the antiferromagnetically ordered state below TN=2.2 K but are replaced by damped spin waves, whose dispersion is much stronger along the c-axis than in other directions. No change is observed in the excitation spectrum or the magnetic order as the system enters the superconducting state below Tc=0.7 K.