Superconductivity in TlBi2 with a large Kadowaki-Woods ratio

In this paper, the superconducting and normal state properties of TlBi2 with the AlB2-type structure were studied by resistivity, magnetization, and specific heat measurements. It was found that bulk superconductivity with Tc = 6.2 K emerges in TlBi2, which is a phonon-mediated s-wave superconductor with a strong electron-phonon coupling (lambda ep = 1.38) and a large superconducting gap (A0/kBTc = 2.25). We found that the p(T) exhibits an unusual T-linear dependence above 50 K, and can be well described by the Fermi-liquid theory below 20 K. Interestingly, its Kadowaki-Woods ratio A/gamma 2 [9.2 x 10-5 mu Q cm(mol K2/mJ)2] is unexpectedly one order of magnitude larger than that obtained in many heavy fermion compounds, although the electronic correlation is not so strong.

Automated summary

This paper investigates the superconducting and normal state properties of TlBi2 with the AlB2-type structure. It is found that TlBi2 exhibits bulk superconductivity and is a phonon-mediated s-wave superconductor. Furthermore, the study reveals that the temperature dependence of the resistivity, p(T), shows a linear relationship at high temperatures and can be described by the Fermi-liquid theory at low temperatures. Interestingly, the Kadowaki-Woods ratio of TlBi2 is unexpectedly large compared to many heavy fermion compounds.