Enhanced weak superconductivity in trigonal $\gamma$-PtBi${}_2$

Abstract

Electrical resistivity experiments show superconductivity at $T_c=1.1$K in a high-quality single crystal of trigonal $\gamma$-PtBi${}_2$, with an enhanced critical magnetic field ${\mu }_0{H}_{c2}(0)\gtrsim 1.5$Tesla and a low critical current-density $J_c(0)\approx 40\mathrm{A}/{\mathrm{cm}}^2$ at $H=0$. Both $T_c$ and $H_{c2}(0)$ are the highest reported values for stoichiometric bulk samples at ambient pressure. We found a weak $H_{c2}$ anisotropy with $\Gamma =H_{c2}^{ab}/H_{c2}^c<1$, which is unusual among superconductors. Under a magnetic field, the superconducting transition becomes broader and asymmetric. Along with the low critical currents, this observation suggests an inhomogeneous superconducting state. In fact, no trace of superconductivity is observed through field-cooling--zero-field-cooling magnetization experiments.

7 pages, 6 figures

References in corpus (3)

• Specific heat evidence for two-gap superconductivity in ternary-iron silicide Lu${}_2$Fe${}_3$Si${}_5$
• Fragility of Fermi arcs in Dirac semimetals
• Observation of Dirac surface states in the hexagonal PtBi2, a possible origin of the linear magnetoresistance

Cited by in corpus (8)

• Electronic structure of the surface superconducting Weyl semimetal PtBi${}_2$
• Fermi arcs dominating the electronic surface properties of trigonal PtBi${}_2$
• Superconductivity in Two-Dimensional Systems with Unconventional Rashba Bands
• Self-consistent surface superconductivity in time-reversal symmetric Weyl semimetals
• Phonon-mediated intrinsic topological superconductivity in Fermi arcs
• Ginzburg-Landau theory for unconventional surface superconductivity in PtBi${}_2$
• Interplay between inversion and translation symmetries in trigonal PtBi${}_2$
• Higher-order topological superconductivity in type-II time-reversal-symmetric Weyl semimetals with a hybrid pairing