English

Threefold error in the reported zero-field cooled magnetic moment of single crystal $La_2SmNi_2O_7$

Superconductivity 2026-02-27 v1

Abstract

For a relatively long time, the observation of the DC diamagnetic state in highly compressed nickelate superconductors [1],[2] has been a challenging experimental problem. And recently Li et al.[3] reported on the measurements of the DC diamagnetism in zero-field-cooled (ZFC) and field-cooled (FC) pressurized single crystal La2SmNi2O7La_2SmNi_2O_7. From the analysis of experimental data, Li et al.[3] reported that the superconducting phase fraction in their La2SmNi2O7La_2SmNi_2O_7 sample measured in the ZFC mode is 62.1%, and the superconducting phase fraction in the FC mode is 14.4%. It should be clarified that we regard the measurements of the DC diamagnetic state [3] in La2SmNi2O7La_2SmNi_2O_7 (and more recently in Pr4Ni3O10Pr_4Ni_3O_{10} [4]) as outstanding experimental results confirming bulk superconductivity in pressurized nickelates. However, we should note that Li et al.[3] made a threefold error in their calculations of the superconducting phase fraction in La2SmNi2O7La_2SmNi_2O_7. We believe that correcting this and other errors in Ref.[3] will benefit the physics community.

Keywords

Cite

@article{arxiv.2602.23240,
  title  = {Threefold error in the reported zero-field cooled magnetic moment of single crystal $La_2SmNi_2O_7$},
  author = {Aleksandr V. Korolev and Evgeny F. Talantsev},
  journal= {arXiv preprint arXiv:2602.23240},
  year   = {2026}
}