Conventional Superconductivity in Type II Dirac Semimetal PdTe${}_2$

Abstract

The transition metal dichalcogenide PdTe${}_2$ was recently shown to be a unique system where a type II Dirac semimetallic phase and a superconducting phase co-exist. This observation has led to wide speculation on the possibility of the emergence of an unconventional topological superconducting phase in PdTe${}_2$. Here, through direct measurement of the superconducting energy gap by scanning tunneling spectroscopy (STS), and temperature and magnetic field evolution of the same, we show that the superconducting phase in PdTe${}_2$ is conventional in nature. The superconducting energy gap is measured to be 326 $\mu$eV at 0.38 K and it follows a temperature dependence that is well described within the framework of Bardeen-Cooper-Schriefer's (BCS) theory of conventional superconductivity. This is surprising because our quantum oscillation measurements confirm that at least one of the bands participating in transport has topologically non-trivial character.

Accepted for publication in Physical Review B

References in corpus (13)

• Majorana Fermions and a Topological Phase Transition in Semiconductor-Superconductor Heterostructures
• Classification of topological insulators and superconductors in three spatial dimensions
• Non-Abelian quantum order in spin-orbit-coupled semiconductors: The search for topological Majorana particles in solid state systems
• Pressure induced Superconductivity in Topological Compound Bi2Te3
• A Majorana smoking gun for the superconductor-semiconductor hybrid topological system
• Type-II Dirac fermions in the PtSe${}_2$ class of transition metal dichalcogenides
• Momentum-Resolved Landau-Level Spectroscopy of Dirac Surface State in Bi2Se3
• Edge-mode Superconductivity in a Two Dimensional Topological Insulator
• A road to reality with topological superconductors
• Type I superconductivity in the Dirac semimetal PdTe2
• Mesoscopic superconductivity and high spin polarization coexisting at metallic point contacts on the Weyl semimetal TaAs
• Unexpected superconductivity at nanoscale junctions made on the topological crystalline insulator Pb${}_{0.6}$Sn${}_{0.4}$Te
• Superconducting and normal-state anisotropy of the doped topological insulator Sr${}_{0.1}$Bi${}_2$Se${}_3$

Cited by in corpus (3)

• Experimental Progress on Layered Topological Semimetals
• Single full gap with mixed type-I and type-II superconductivity on surface of the type-II Dirac semimetal PdTe2 by point-contact spectroscopy
• Dominant $s$-wave superconducting gap in PdTe${}_2$ observed by tunneling spectroscopy on side-junctions