Dirac-Fermion-Induced Parity Mixing in Superconducting Topological Insulators

Abstract

We self-consistently study surface states of superconducting topological insulators. We clarify that, if a topologically trivial bulk s-wave pairing symmetry is realized, parity mixing of pair potential near the surface is anomalously enhanced by surface Dirac fermions, opening an additional surface gap larger than the bulk one. In contrast to classical s-wave superconductors, the resulting surface density of state hosts an extra coherent peak at the induced gap besides a conventional peak at the bulk gap. We also find that no such extra peak appears for odd-parity superconductors with a cylindrical Fermi surface. Our calculation suggests that the simple U-shaped scanning tunneling microscope spectrum in Cu${}_x$Bi${}_2$Se${}_3$ does not originate from s-wave superconductivity, but can be explained by odd-parity superconductivity with a cylindrical Fermi surface.

12 pages, 11 figures, published version

References in corpus (21)

• Topological Insulators with Inversion Symmetry
• Classification of topological insulators and superconductors in three spatial dimensions
• Dissipationless Quantum Spin Current at Room Temperature
• Topological Phases of Noncentrosymmetric Superconductors: Edge States, Majorana Fermions, and the Non-Abelian Statistics
• SU(2) Non-Abelian Holonomy and Dissipationless Spin Current in Semiconductors
• Odd-parity topological superconductor with nematic order: Application to CuxBi2Se3
• Topological spin-current in non-centrosymmetric superconductors
• Local Measurements of the Superconducting Pairing Symmetry in CuxBi2Se3
• Odd-Parity Pairing and Topological Superconductivity in a Strongly Spin-Orbit Coupled Semiconductor
• Topological properties of spin-triplet superconductors and the Fermi surface topology in the normal state
• Anomalous Andreev bound state in non-centrosymmetric superconductors
• Unusual nature of fully-gapped superconductivity in In-doped SnTe
• Surface density of states and topological edge states in non-centrosymmetric superconductors
• Evolution of the fermi surface of a doped topological insulator with carrier concentration
• Surface spectral function in the superconducting state of a topological insulator
• Splitting and oscillation of Majorana zero modes in the p-wave BCS-BEC evolution with plural vortices
• Multi-band effects on Fulde-Ferrell-Larkin-Ovchinnikov states of Pauli-limited superconductors
• Quasi-classical theory of tunneling spectroscopy in superconducting topological insulator
• Anomalous Josephson current in superconducting topological insulator
• Effect of Fermi surface evolution on superconducting gap in superconducting topological insulator
• Surface states and local spin susceptibility in doped three-dimensional topological insulators with odd-parity superconducting pairing symmetry

Cited by in corpus (41)

• Topological superconductors: a review
• Topological Crystalline Insulators and Topological Superconductors: From Concepts to Materials
• Majorana Fermions and Topology in Superconductors
• Spin-Rotation Symmetry Breaking in the Superconducting State of CuxBi2Se3
• Thermodynamic evidence for nematic superconductivity in Cu${}_x$Bi${}_2$Se${}_3$
• Superconducting Topological Surface States in Non-centrosymmetric Bulk Superconductor PbTaSe2
• Topological superconductivity in Dirac semimetals
• Topologically protected surface states in a centrosymmetric superconductor beta-PdBi2
• Symmetry Protected Topological Superfluids and Superconductors --- From the Basics to ${}^3$He ---
• Nematic superconductivity in doped Bi2Se3 topological superconductors
• Experimental Observation of Topological Superconductivity and Majorana Zero Modes on beta-Bi2Pd Thin Films
• Topological quantum states of matter in iron-based superconductors: From concepts to material realization
• Direct visualization of the nematic superconductivity in Cu${}_x$Bi${}_2$Se${}_3$
• Surface Superconductivity in the type II Weyl Semimetal TaIrTe4
• Superconductivity in doped Dirac semimetals
• Symmetry Protected Topological Superfluid ${}^3$He-B
• Superconducting doped topological materials
• Fragile surface zero-energy flat bands in three-dimensional chiral superconductors
• Dependence of superconductivity in CuxBi2Se3 on quenching conditions
• Non-fragile superconductivity with nodes in the superconducting topological insulator CuxBi2Se3: Zeeman orbital field and non-magnetic impurities
• Topology and symmetry of surface Majorana arcs in cyclic superconductors
• Single full gap with mixed type-I and type-II superconductivity on surface of the type-II Dirac semimetal PdTe2 by point-contact spectroscopy
• Chiral Higgs Mode in Nematic Superconductors
• Time-reversal-invariant topological superconductivity in n-doped BiH
• Experimental evidence of anomalously large superconducting gap on topological surface state of $\beta$-$\mathbf{B}{\mathbf{i}}_2\mathbf{Pd}$ film
• Transport evidence for three dimensional topological superconductivity in doped $\beta$-PdBi${}_2$
• Topological Crystalline Superconductivity in Dirac Semimetal Phase of Iron-based Superconductors
• Spin-singlet superconductivity in doped topological crystalline insulator Sn_{0.96}In_{0.04}Te
• Nematic superconductivity in Cu${}_x$Bi${}_2$Se${}_3$: The surface Andreev bound states
• Pressure-induced superconductivity in the three-dimensional Dirac semimetal Cd3As2
• Superconductivity in Cu-doped Bi${}_2$Se${}_3$ with potential disorder
• Superconductivity near the saddle point in the two-dimensional Rashba system Si(111)-$\sqrt{3}\times \sqrt{3}$-(Tl,Pb)
• Emergence of Surface Superconductivity through Interference in Superconducting-proximity Topological Insulators
• Inverse coherence effects in nuclear magnetic relaxation rates as a sign of topological superconductivity
• Odd-frequency pairs and anomalous proximity effect in nematic and chiral states of superconducting topological insulators
• Direct observation of the surface superconducting gap in the topological superconductor candidate β-PdBi2
• Tsunami Solitons Emerging from Superconducting Gap
• Intrinsic chiral topological superconductor thin films
• Particle-hole spectral asymmetry at the edge of multiorbital noncentrosymmetric superconductors
• Theory of low-energy behaviors in topological $s$-wave pairing superconductors
• Pairing symmetries in the Zeeman-coupled extended attractive Hubbard model