Publication Date

7-1-2018

Department

Ames Laboratory; Physics and Astronomy

Campus Units

Physics and Astronomy, Ames Laboratory

Report Number

IS-J 9708

DOI

10.1103/PhysRevB.98.024508

Journal Title

Physical Review B

Volume Number

98

Issue Number

2

First Page

024508

Abstract

Superconducting gap structure was probed in type-II Dirac semimetal PdTe2 by measuring the London penetration depth using the tunnel diode resonator technique. At low temperatures, the data for two samples are well described by a weak-coupling exponential fit yielding λ(T=0)=230 nm as the only fit parameter at a fixed Δ(0)/Tc≈1.76, and the calculated superfluid density is consistent with a fully gapped superconducting state characterized by a single gap scale. Electrical resistivity measurements for in-plane and inter-plane current directions find very low and nearly temperature-independent normal-state anisotropy. The temperature dependence of resistivity is typical for conventional phonon scattering in metals. We compare these experimental results with expectations from a detailed theoretical symmetry analysis and reduce the number of possible superconducting pairing states in PdTe2 to only three nodeless candidates: a regular, topologically trivial s-wave pairing, and two distinct odd-parity triplet states that both can be topologically nontrivial depending on the microscopic interactions driving the superconducting instability.

Language

en

Department of Energy Subject Categories

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY

Publisher

Iowa State University Digital Repository, Ames IA (United States)

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