Spin current in topologically trivial and nontrivial noncentrosymmetric superconductors

Abstract

We study theoretically the surface of time-reversal-symmetric, noncentrosymmetric superconductor with mixed singlet and triplet order parameters. A pair of counterpropagating subgap quasiparticle surface bound states with opposite spin projections are obtained in the nontrivial Z${}_2$ case where the triplet component is larger than the singlet one, contributing to a spin current. In contrast to the pure p-wave cases, these subgap states do not have a fixed spin projections but depend on the momenta along the surface. In the trivial Z${}_2$ case where the singlet order parameter is larger, no subgap surface bound states show up. In both cases, there is also a finite contribution to the spin current from the continuum states with energies between the two gaps. The method for obtaining the quasiclassical Green's functions associated with the noncentrosymmetric superconductors is also presented.

Accepted version

References in corpus (28)

• Quantum Spin Hall Effect in Graphene
• Quantum Spin Hall Effect and Topological Phase Transition in HgTe Quantum Wells
• $Z_2$ Topological Order and the Quantum Spin Hall Effect
• Topological Insulators in Three Dimensions
• Topological Insulators with Inversion Symmetry
• Discovery (theoretical prediction and experimental observation) of a large-gap topological-insulator class with spin-polarized single-Dirac-cone on the surface
• Paired states of fermions in two dimensions with breaking of parity and time-reversal symmetries, and the fractional quantum Hall effect
• First direct observation of Spin-textures in Topological Insulators : Spin-resolved ARPES as a probe of topological quantum spin Hall effect and Berry's phase
• Superconducting 2D system with lifted spin degeneracy: Mixed singlet-triplet state
• The Quantum Spin Hall Effect: Theory and Experiment
• Superconductivty without inversion symmetry: MnSi versus CePt_3Si
• S-wave/spin-triplet order in superconductors without inversion symmetry: Li${}_2$Pd${}_3$B and Li${}_2$Pt${}_3$B
• Spin Hall Insulator
• Fermi Surface Topological Invariants for Time Reversal Invariant Superconductors
• Edge modes, edge currents, and gauge invariance in $p_x+i{p}_y$ superfluids and superconductors
• Topological spin-current in non-centrosymmetric superconductors
• 2D superconductivity with strong spin-orbit interaction
• Surface bound states and spin currents in non-centrosymmetric superconductors
• Andreev bound states and tunneling characteristics of a non-centrosymmetric superconductor
• Temperature Dependence of the Superfluid Density in a Noncentrosymmetric Superconductor
• The scattering problem in non-equilibrium quasiclassical theory of metals and superconductors: general boundary conditions and applications
• Spin current and spin accumulation near a Josephson junction between a singlet and triplet superconductor
• Zero-energy vortex bound states in noncentrosymmetric superconductors
• Signature of superconducting states in cubic crystal without inversion symmetry
• Mixed-parity superconductivity in centrosymmetric crystals
• Supercurrent and noise in point contact between two different superconductors
• Wavefunction topology of two-dimensional time-reversal symmetric superconductors
• ac Josephson effect in asymmetric superconducting quantum point contacts

Cited by in corpus (25)

• Superconductivity and spin-orbit coupling in non-centrosymmetric materials: a review
• Superconductivity in the topological semimetal YPtBi
• Topological surface states in nodal superconductors
• Types of topological surface states in nodal noncentrosymmetric superconductors
• Observation of the spin-polarized surface state in a noncentrosymmetric superconductor BiPd
• Superconducting Properties of the Non-Centrosymmetric Superconductor Re6Hf
• Proximity effect with noncentrosymmetric superconductors
• Edge currents as a signature of flat bands in topological superconductors
• Switching a polar metal via strain gradients
• BCS-like superconductivity in the noncentrosymmetric compounds Nb${}_x$Re${}_{1-x}$
• Anisotropic superconductivity in the noncentrosymmetric BiPd
• Transport signatures of superconducting hybrids with mixed singlet and chiral triplet states
• 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
• Spin Currents and Spontaneous Magnetization at Twin Boundaries of Noncentrosymmetric Superconductors
• Upward curvature of the upper critical field and the V-shaped pressure dependence of $T_c$ in the noncentrosymmetric superconductor PbTaSe${}_2$
• Helical spin texture of surface states in topological superconductors
• Helical Majorana surface states of strongly disordered topological superconductors with time-reversal symmetry
• Transport and noise properties of a normal metal-superconductor-normal metal junction with mixed singlet and chiral triplet pairings
• Ginzburg-Landau description of twin boundaries in noncentrosymmetric superconductors
• Interface currents and magnetization in singlet-triplet superconducting heterostructures: Role of chiral and helical domains
• Mixed-parity superconductivity near Lifshitz transitions in strongly spin-orbit-coupled metals
• Impurity Effect on the Local Density of States around a Vortex in Noncentrosymmetric Superconductors
• Discovery of the topological surface state in a noncentrosymmetric superconductor BiPd