Topologically protected flat zero-energy surface bands in non-centrosymmetric superconductors

Abstract

Nodal non-centrosymmetric superconductors (NCS) have recently been shown to be topologically non-trivial. An important consequence is the existence of topologically protected flat zero-energy surface bands, which are related to the topological characteristics of the line nodes of the bulk gap via a bulk-boundary correspondence [Schnyder and Ryu, arXiv:1011.1438]. In this paper we examine these zero-energy surface bands using a quasiclassical theory. We determine their spectrum and derive a general condition for their existence in terms of the sign change of the gap functions. A key experimental signature of the zero-energy surface bands is a zero-bias peak in the tunneling conductance, which depends strongly on the surface orientation. This can be used as a fingerprint of a topologically non-trivial NCS.

4 pages, 2 figures

References in corpus (19)

• Topological Insulators
• Topological insulators and superconductors: ten-fold way and dimensional hierarchy
• Heavy fermion superconductivity and magnetic order in non-centrosymmetric $CeP{t}_{3}Si$
• Superconductivty without inversion symmetry: MnSi versus CePt_3Si
• Three-Dimensional Topological Insulators
• Topology of Andreev Bound States with Flat Dispersion
• Superconductivity in metal rich Li-Pd-B ternary Boride
• Topological spin-current in non-centrosymmetric superconductors
• Dimensional crossover in topological matter: Evolution of the multiple Dirac point in the layered system to the flat band on the surface
• Anomalous Andreev bound state in non-centrosymmetric superconductors
• Surface density of states and topological edge states in non-centrosymmetric superconductors
• Majorana Fermions in Nodal Superconductors: Gapless Topological Phase
• Surface bound states and spin currents in non-centrosymmetric superconductors
• Nodal Structure of Superconductors with Time-Reversal Invariance and Z2 Topological Number
• Topologically stable gapless phases of time-reversal invariant superconductors
• Andreev bound states and tunneling characteristics of a non-centrosymmetric superconductor
• Flat band in the core of topological defects: bulk-vortex correspondence in topological superfluids with Fermi points
• Spin-orbit coupling and semiclassical electron dynamics in noncentrosymmetric metals
• Intrinsically s-wave like property of triplet superconductors with spin-orbit coupling

Cited by in corpus (80)

• Classification of topological quantum matter with symmetries
• Topological superconductors: a review
• Symmetry and Topology in Superconductors - Odd-frequency pairing and edge states -
• Classification of reflection symmetry protected topological semimetals and nodal superconductors
• Dirac and Weyl Superconductors in Three Dimensions
• Protected boundary states in gapless topological phases
• Topological surface states in nodal superconductors
• Types of topological surface states in nodal noncentrosymmetric superconductors
• Bogoliubov Fermi surfaces: General theory, magnetic order, and topology
• High-temperature surface superconductivity in rhombohedral graphite
• Topological Blount's theorem of odd-parity superconductors
• Majorana Flat Bands and Uni-directional Majorana Edge States in Gapless Topological Superconductors
• Inflated nodes and surface states in superconducting half-Heusler compounds
• Topological charges of three-dimensional Dirac semimetals with rotation symmetry
• Superconductivity in doped Dirac semimetals
• Momentum-space structure of surface states in a topological semimetal with a nexus point of Dirac lines
• Topologically stable gapless phases in nonsymmorphic superconductors
• Three-Dimensional Majorana Fermions in Chiral Superconductors
• Topological phase transitions in multi-component superconductors
• Theory of Tunneling Spectroscopy in Unconventional $p$-wave Magnet-Superconductor Hybrid Structures
• Proximity effect with noncentrosymmetric superconductors
• Edge currents as a signature of flat bands in topological superconductors
• Fragile surface zero-energy flat bands in three-dimensional chiral superconductors
• Experimental consequences of Bogoliubov Fermi surfaces
• Inter-orbital topological superconductivity in spin-orbit coupled superconductors with inversion symmetry breaking
• Symmetry-protected line nodes and Majorana flat bands in nodal crystalline superconductors
• Odd-Frequency Pairs in Chiral Symmetric Systems: Spectral Bulk-Boundary Correspondence and Topological Criticality
• Singlet-Quintet Mixing in Spin-Orbit Coupled Superconductors with j=3/2 Fermions
• Majorana surface modes of nodal topological pairings in spin-$\frac{3}{2}$ semi-metals
• Surface electronic state of superconducting topological crystalline insulator
• Transport signatures of superconducting hybrids with mixed singlet and chiral triplet states
• Theory of quasiparticle scattering interference on the surface of topological superconductors
• Majorana multipole response of topological superconductors
• Majorana fermions in s-wave noncentrosymmetric superconductor with Rashba and Dresselhaus (110) spin-orbit couplings
• Stability of flat-band edge states in topological superconductors without inversion center
• Evolution of Edge States and Critical Phenomena in the Rashba Superconductor with Magnetization
• Coexistence of nontrivial topological properties and strong ferromagnetic fluctuations in $A_2$Cr${}_3$As${}_3$ ($A$=Na, K, Rb and Cs)
• Spin Berry phase in the Fermi arc states
• Magnetically robust topological edge states and flat bands
• Interface currents in topological superconductor-ferromagnet heterostructures
• Zeeman field induced topological phase transitions in triplet superconductors
• Josephson Effect in Noncentrosymmetric Superconductor Junctions
• From Dirac semimetals to topological phases in three dimensions: a coupled wire construction
• Anomalous thermodynamic power laws near topological transitions in nodal superconductors
• Classification of crystalline topological semimetals with an application to Na${}_3$Bi
• Helical spin texture of surface states in topological superconductors
• Majorana vortex-bound states in three-dimensional nodal noncentrosymmetric superconductors
• Anomalous Josephson Coupling and High-Harmonics in Non-Centrosymmetric Superconductors with $S$-wave Spin-Triplet Pairing
• Orbital tunable 0-$\pi$ transitions in Josephson junctions with noncentrosymmetric topological superconductors
• Unconventional superconductivity and Surface pairing symmetry in Half-Heusler Compounds
• Topological Phase Transitions in Line-nodal Superconductors
• Probing Majorana Flat Bands in Nodal $d_{x^2-y^2}$-wave Superconductors with Rashba Spin-Orbit Coupling
• Helical Majorana surface states of strongly disordered topological superconductors with time-reversal symmetry
• Stability of flat zero-energy states at the dirty surface of a nodal superconductor
• Scattering theory of topological invariants in nodal superconductors
• Surface instability in nodal noncentrosymmetric superconductors
• Topological flat bands in optical checkerboard-like lattices
• Spin-Orbital Hallmarks of Unconventional Superconductors Without Inversion Symmetry
• Fully gapped superconductivity in centrosymmetric and non-centrosymmetric Re-B compounds probed with $\mu$SR
• Edge currents as a probe of the strongly spin-polarized topological noncentrosymmetric superconductors
• Symmetry conditions of a nodal superconductor for generating robust flat-band Andreev bound states at its dirty surface
• Generalized Fermion Doubling Theorems: Classification of 2D Nodal Systems in Terms of Wallpaper Groups
• Appearance of flat surface bands in three-dimensional topological insulators in a ferromagnetic exchange field
• Dynamical bulk-edge correspondence for nodal lines in parameter space
• Surface density of states and tunneling spectroscopy of a spin-3/2 superconductor with Bogoliubov Fermi Surfaces
• Nearly flat Andreev bound states in superconductor-topological insulator hybrid structures
• Intrinsic topological superconductivity with exactly flat surface bands in the quasi-one-dimensional A${}_2$Cr${}_3$As${}_3$ (A=Na, K, Rb, Cs) superconductors
• Topological nodal superconducting phases and topological phase transition in the hyperhoneycomb lattice
• Orbital hybridized topological Fulde-Ferrel superfluidity in a noncentrosymmetric optical lattice
• Tunneling conductance in superconducting junctions with $p$-wave unconventional magnets breaking time-reversal symmetry
• Topological quantum phase transitions in the spin-singlet superconductor with Rashba and Dresselhaus (110) spin-orbit couplings
• Interacting Majorana modes at surfaces of noncentrosymmetric superconductors
• Theory of surface spectroscopy for noncentrosymmetric superconductors
• Complete zero-energy flat bands of surface states in fully gapped chiral noncentrosymmetric superconductors
• Critical behavior around the fixed points driven by fermion-fermion interactions and disorders in the nodal-line superconductors
• Manipulation of Majorana wave packets at surfaces of nodal noncentrosymmetric superconductors
• Nuclear spin relaxation rate of nonunitary Dirac and Weyl superconductors
• Particle-hole spectral asymmetry at the edge of multiorbital noncentrosymmetric superconductors
• Emergence of a new symmetry class for Bogoliubov-de Gennes (BdG) Hamiltonians: Expanding ten-fold symmetry classes
• Majorana flat bands at structured surfaces of nodal noncentrosymmetric superconductors