We present muon spin rotation and relaxation (muSR) measurements as well as demagnetising field corrected magnetisation measurements on polycrystalline samples of the noncentrosymmetric superconductor BeAu. From muSR measurements in a transverse field, we determine that BeAu is a type-I superconductor with Hc = 256 Oe, amending the previous understanding of the compound as a type-II superconductor. To account for demagnetising effects in magnetisation measurements, we produce an ellipsoidal sample, for which a demagnetisation factor can be calculated. After correcting for demagnetising effects, our magnetisation results are in agreement with our muSR measurements. Using both types of measurements we construct a phase diagram from T = 30 mK to Tc = 3.25 K. We then study the effect of hydrostatic pressure and find that 450 MPa decreases Tc by 34 mK, comparable to the change seen in type-I elemental superconductors Sn, In and Ta, suggesting BeAu is far from a quantum critical point accessible by the application of pressure.
@article{arxiv.1902.00073,
title = {muSR and Magnetometry Study of the Type-I Superconductor BeAu},
author = {James Beare and Matthew Nugent and Murray Wilson and Yipeng Cai and Timothy Munsie and Alfred Amon and Andreas Leithe-Jasper and Zizhou Gong and Shengli Guo and Zurab Guguchia and Yuri Grin and Yasutomo Uemura and Eteri Svanidze and Graeme Luke},
journal= {arXiv preprint arXiv:1902.00073},
year = {2019}
}