Scattering theory of topological invariants in nodal superconductors
arXiv:1208.5491 · doi:10.1103/PhysRevB.86.174520
Abstract
Time-reversal invariant superconductors having nodes of vanishing excitation gap support zero-energy boundary states with topological protection. Existing expressions for the topological invariant are given in terms of the Hamiltonian of an infinite system. We give an alternative formulation in terms of the Andreev reflection matrix of a normal-metal-superconductor interface. This allows to relate the topological invariant to the angle-resolved Andreev conductance, also when the boundary state in the superconductor has merged with the continuum of states in the normal metal. A variety of symmetry classes is obtained, depending on additional unitary symmetries of the reflection matrix. We derive conditions for the quantization of the conductance in each symmetry class and test these on a model for a 2D or 3D superconductor with spin-singlet and spin-triplet pairing, mixed by Rashba spin-orbit interaction.
arXiv comment11 pages, 10 figures
References in corpus (23)
- Topological Insulators
- Topological insulators and superconductors
- Novel Symmetry Classes in Mesoscopic Normal-Superconducting Hybrid Structures
- Topological insulators and superconductors: ten-fold way and dimensional hierarchy
- Topological Crystalline Insulators
- Majorana fermions in a tunable semiconductor device
- Topology of Andreev Bound States with Flat Dispersion
- Midgap edge states and pairing symmetry of quasi-one-dimensional organic superconductors
- Flat bands in topological media
- Topological phases and surface flat bands in superconductors without inversion symmetry
- Topological spin-current in non-centrosymmetric superconductors
- Scattering formula for the topological quantum number of a disordered multi-mode wire
- Scattering theory of topological insulators and superconductors
- Anomalous Andreev bound state in non-centrosymmetric superconductors
- Types of topological surface states in nodal noncentrosymmetric superconductors
- Surface density of states and topological edge states in non-centrosymmetric superconductors
- Nodal Structure of Superconductors with Time-Reversal Invariance and Z2 Topological Number
- Topologically protected flat zero-energy surface bands in non-centrosymmetric superconductors
- Topologically stable gapless phases of time-reversal invariant superconductors
- Angle dependence of Andreev scattering at semiconductor-superconductor interfaces
- Andreev reflection from a topological superconductor with chiral symmetry
- Andreev spectroscopy and surface density of states for a three-dimensional time-reversal invariant topological superconductor
- Dephasing-enabled triplet Andreev conductance
Cited by in corpus (14)
- Protected boundary states in gapless topological phases
- Topological surface states in nodal superconductors
- Scattering theory of topological phases in discrete-time quantum walks
- Edge currents as a signature of flat bands in topological superconductors
- Quantization of Conductance Minimum and Index Theorem
- Zero-bias conductance peak in detached flakes of superconducting 2H-TaS probed by scanning tunneling spectroscopy
- Theory of quasiparticle scattering interference on the surface of topological superconductors
- Stability of flat-band edge states in topological superconductors without inversion center
- Interface currents in topological superconductor-ferromagnet heterostructures
- Helical spin texture of surface states in topological superconductors
- Phase-locked magnetoconductance oscillations as a probe of Majorana edge states
- Helical Majorana surface states of strongly disordered topological superconductors with time-reversal symmetry
- Edge currents as a probe of the strongly spin-polarized topological noncentrosymmetric superconductors
- Majorana bound states in d-wave superconductor-based hybrid systems