arXiv subjects

Alex H. Mayo

Publications and source records attributed to Alex H. Mayo.

3 recordsLinked to original sources

arXiv2025

Anisotropic Magnetism in Gd$_2$B$_5$

We report the synthesis of single crystals of Gd$_2$B$_5$ through a ruthenium-gadolinium flux method. The Gd$_2$B$_5$ system is a member of the monoclinic $P21/c$ (No. 14) space group and realizes lattices of gadolinium atoms in the $(1\,0\,0)$ plane. We characterized the sample through orientation-dependent electrical transport, magnetization, magnetic torque, and heat capacity measurements to probe the magnetic anisotropy of the system and map out its phase diagram. Gd$_2$B$_5$ realizes two zero-field ordered phases M$_1$ and M$_2$, as well as a third field-induced ordered phase M$_\perp$ arising when the magnetic field is applied in the $(1\,0\,0)$ plane.

cond-mat.mes-hall↗

arXiv2023

Superconductivity in a ferroelectric-like topological semimetal SrAuBi

Given the rarity of metallic systems that exhibit ferroelectric-like transitions, it is apparently challenging to find a system that simultaneously possesses superconductivity and ferroelectric-like structural instability. Here, we report the observation of superconductivity at 2.4 K in a layered semimetal SrAuBi characterized by strong spin-orbit coupling (SOC) and ferroelectric-like lattice distortion. Single crystals of SrAuBi have been successfully synthesized and found to show a polar-nonpolar structure transition at 214 K, which is associated with the buckling of Au-Bi honeycomb lattice. On the basis of the band calculations considering SOC, we found significant Rashba-type spin splitting and symmetry-protected multiple Dirac points near the Fermi level. We believe that this discovery opens up new possibilities of pursuing exotic superconducting states associated with the semimetallic band structure without space inversion symmetry and the topological surface state with the strong SOC.

cond-mat.supr-con↗

arXiv2022

Superconductivity in a Magnetic Rashba Semimetal EuAuBi

We report the observation of superconductivity with multiple magnetic ordering and Rashba-type spin-orbit coupling in a layered polar semimetal EuAuBi. Magnetic transition is observed at 4 K, followed by a superconducting transition at 2.2 K, which is sensitive to the crystal surface conditions. The upper critical field Hc2 of 9.8 T for the out-of-plane field is three times higher than that for the in-plane field, which can be associated with the two-dimensional structure or the surface state. On the basis of first-principles calculations, it is found that the characteristic Hc2 possibly reflects the anisotropic modification of the Fermi surface by the effective combination of Rashba-type spin splitting and Zeeman spin splitting enhanced by Eu moments.

cond-mat.supr-con↗