Solitonic in-gap modes in a superconductor-quantum antiferromagnet interface

Abstract

Bound states at interfaces between superconductors and other materials are a powerful tool to characterize the nature of the involved systems, and to engineer elusive quantum excitations. In-gap excitations of conventional s-wave superconductors occur, for instance, at magnetic impurities with net magnetic moment breaking time-reversal symmetry. Here we show that interfaces between a superconductor and a quantum antiferromagnet can host robust in-gap excitations, without breaking time-reversal symmetry. We illustrate this phenomenon in a one-dimensional model system with an interface between a conventional s-wave superconductor and a one-dimensional Mott insulator described by a standard Hubbard model. This genuine many-body problem is solved exactly by employing a combination of kernel polynomial and tensor network techniques. We unveil the nature of such zero modes by showing that they can be adiabatically connected to solitonic solutions between a superconductor and a classical antiferromagnet. Our results put forward a new class of in-gap excitations between superconductors and a disordered quantum spin phase can be relevant for a wider range of heterostructures.

10 pages, 10 figures

References in corpus (13)

• Superconducting proximity effect and Majorana fermions at the surface of a topological insulator
• Majorana Fermions and a Topological Phase Transition in Semiconductor-Superconductor Heterostructures
• Observation of Majorana Fermions in Ferromagnetic Atomic Chains on a Superconductor
• The Kernel Polynomial Method
• Anomalous Andreev bound state in non-centrosymmetric superconductors
• Orbital Picture of Yu-Shiba-Rusinov Multiplets
• Engineering the eigenstates of coupled spin-1/2 atoms on a surface
• Chebyshev Matrix Product State Impurity Solver for the Dynamical Mean-Field Theory
• Spectral functions and time evolution from the Chebyshev recursion
• Proximity-induced Shiba states in a molecular junction
• An exactly solvable BCS-Hubbard Model in arbitrary dimensions
• Andreev Bound states in One Dimensional Topological Superconductor
• Spin Andreev-like reflection in metal-Mott insulator heterostructures

Cited by in corpus (9)

• Designing quantum many-body matter with conditional generative adversarial networks
• Inducing a many-body topological state of matter through Coulomb-engineered local interactions
• Real-space imaging of dispersive triplon excitations in engineered quantum magnets
• Quasiperiodic criticality and spin-triplet superconductivity in superconductor-antiferromagnet moire patterns
• Interaction-induced topological superconductivity in antiferromagnet-superconductor junctions
• Dynamical topological excitations in parafermion chains
• Neural network enhanced hybrid quantum many-body dynamical distributions
• Many-body Majorana-like zero modes without gauge symmetry breaking
• Real-space spectral simulation of quantum spin models: Application to generalized Kitaev models