Fully gapped superconductivity in the topological superconductor beta-PdBi2

Abstract

The recent discovery of the topologically protected surface states in the beta-phase of PdBi2 has reignited the research interest in this class of superconductors. Here, we show results of our muon spin relaxation and rotation (muSR) measurements carried out to investigate the superconducting and magnetic properties and the topological effect in the superconducting ground state of beta-PdBi2. Zero-field muSR data reveal that no sizeable spontaneous magnetization arises with the onset of superconductivity implying that the time reversal symmetry is preserved in the superconducting state of beta-PdBi2. Further, a strong diamagnetic shift of the applied field has been observed in the transverse-field (TF) muSR experiments, indicating that any triplet-pairing channel, if present, does not dominate the superconducting condensate. Using TF-muSR, we estimate that the magnetic penetration depth is 263(10) nm at zero temperature. Temperature dependence of the magnetic penetration depth provides evidence for the existence of a nodeless single s-wave type isotropic energy gap of 0.78(1) meV at zero temperature. Our results further suggest that the topologically protected surface states have no effect on the bulk of the superconductor.

arXiv commentaccepted for publication as a Rapid Communication in Physical Review B

References in corpus (25)

• Time-Reversal Symmetry Breaking Superconductivity in Sr2RuO4
• Superconductivity in CuxBi2Se3 and its implications for pairing in the undoped topological insulator
• Odd-Parity Topological Superconductors: Theory and Application to Cu${}_x$Bi${}_2$Se${}_3$
• Topological Superconductivity in CuxBi2Se3
• musrfit: A free platform-independent framework for muSR data analysis
• Magnetic Penetration Depth in Unconventional Superconductors
• Pressure induced Superconductivity in Topological Compound Bi2Te3
• Properties of the Ideal Ginzburg-Landau Vortex Lattice
• A Sharp Peak of the Zero-Temperature Penetration Depth at Optimal Composition in BaFe2(As1-xPx)2
• Evidence for time-reversal symmetry breaking in the non-centrosymmetric superconductor LaNiC${}_2$
• Bulk superconducting phase with a full energy gap in the doped topological insulator Cu_xBi_2Se_3
• Time-Reversal Symmetry-Breaking Superconductivity in Heavy Fermion PrOs4Sb12 detected by Muon Spin Relaxation
• Odd-Parity Pairing and Topological Superconductivity in a Strongly Spin-Orbit Coupled Semiconductor
• Evidence for Time-Reversal-Symmetry-Broken Superconductivity in Locally Noncentrosymmetric SrPtAs
• Observation of Time-Reversal Symmetry Breaking in the Non-Centrosymmetric Superconductor Re6Zr
• Superconductivity in Topological Insulator Sb2Te3 Induced by Pressure
• Topologically protected surface states in a centrosymmetric superconductor beta-PdBi2
• Non-unitary triplet pairing in the centrosymmetric superconductor LaNiGa${}_2$
• Evidence for time-reversal symmetry breaking in superconducting PrPt4Ge12
• Muon-spin rotation studies of SmFeAsO_0.85 and NdFeAsO_0.85 superconductors
• Absence of zero field muon spin relaxation induced by superconductivity in the B phase of UPt${}_3$
• Superconductivity at 5.4 K in $\beta$-Bi${}_2$Pd
• Magnetic field dependence of the density of states in the multiband superconductor $\beta$-Bi${}_2$Pd
• Single gap superconductivity in beta-Bi2Pd
• Strong enhancement of conventional superconductivity near a quantum critical point of (Ca,Sr)_3Ir_4Sn_13

Cited by in corpus (14)

• Unconventional Superconductivity
• Experimental Observation of Topological Superconductivity and Majorana Zero Modes on beta-Bi2Pd Thin Films
• Synthesis, characterization and physical properties of layered bismuthide PtBi${}_2$
• Electron-phonon coupling and pairing mechanism in $\beta$--Bi${}_2$Pd centrosymmetric superconductor
• Probing the superconducting gap symmetry of $\alpha$-PdBi${}_2$: A penetration depth study
• Evolution of the topologically protected surface states in superconductor $\beta$-Bi${}_2$Pd from the three-dimensional to the two-dimensional limit
• Dirac State in a Centrosymmetric Superconductor alpha-PdBi2
• Unconventional pressure dependence of the superfluid density in the nodeless topological superconductor $\alpha$-PdBi${}_2$
• Superconducting ground state of nonsymmorphic superconducting compound Zr${}_2$Ir
• Multiphase superconductivity in PdBi2
• Topological nodal $i$-wave superconductivity in PtBi${}_2$
• Low-Energy Surface States in the Normal State of $\alpha$-PdBi2 Superconductor
• Superconductivity in Bi based Bi2PdPt
• Absence of superconductivity in topological metal ScInAu${}_2$