Effect of Geomagnetism on 101Ru Nuclear Quadrupole Resonance Measurements of CeRu2

TL;DR

This study demonstrates that geomagnetic fields influence 101Ru NQR measurements in CeRu2, affecting the spin-echo decay at specific transitions and highlighting the importance of magnetic shielding in such experiments.

Contribution

It reveals the sensitivity of 101Ru NQR spin-echo signals to weak magnetic fields and the impact of geomagnetism on measurements in superconducting materials.

Findings

Oscillatory behavior observed at +-1/2 <-> +-3/2 transitions

Disappearance of modulation in superconducting state or with magnetic shielding

NQR decay curve sensitivity to weak magnetic fields

Abstract

We performed 101Ru nuclear quadrupole resonance (NQR) measurements on the s-wave superconductor CeRu2 and found oscillatory behavior in the spin-echo amplitude at the +-1/2 <-> +-3/2 transitions but not at the +-3/2 <-> +-5/2 transitions. The modulation disappears in the superconducting state or in a magnetic shield, which implies a geomagnetic field effect. Our results indicate that the NQR spin-echo decay curve at the +-1/2 <-> +-3/2 transitions is sensitive to a weak magnetic field.