Comment on "Quantum oscillations in nanofabricated rings of spin-triplet superconductor Sr2RuO4"

TL;DR

This paper comments on recent experimental findings of half-quantum vortices in Sr2RuO4, highlighting the importance of in-plane magnetic fields and clarifying previous claims in the context of superconducting quantum phenomena.

Contribution

It provides critical analysis of recent magnetization and magnetotransport measurements in Sr2RuO4, emphasizing the need for in-plane magnetic field considerations and addressing discrepancies in prior interpretations.

Findings

Highlights the importance of in-plane magnetic fields in measurements

Points out incomplete comparisons due to missing experimental ingredients

Clarifies misconceptions in recent experimental claims

Abstract

Recently Jang et al. reported the observation of half-height magnetization steps in cantilever magnetometry measurements of mesoscopic annular Sr2RuO4 particles. Such magnetization features were interpreted as the presence of half-quantum vortices. In an attempt to examine our findings, very recently Cai et al. (1202.3146) have performed magnetotransport measurements of micron-size rings fabricated from small Sr2RuO4 crystals. While fabrication of such samples and subsequent verification of our findings is highly desirable, we would like to point out that, at the current state of affairs, the direct comparison is incomplete partly due to the fact that the measurements of Cai et al. were lacking an important ingredient -- the in-plane magnetic field. We would also like to offer clarification on few questionable statements made by the authors of 1202.3146.