Chiral Majorana Fermions in two dimensional square lattice antiferromagnet with proximity-induced superconductivity

Abstract

Combination of proximity-induced superconductivity and ferromagnetic exchange field in a two-dimensional square-lattice antiferromagnet with spin-orbit coupling and nonsymmorphic symmetry can induce a topological superconductor phase with chiral Majorana edge states. The lattice model of the Bogoliubov-de Gennes (BdG) Hamiltonian was applied to study the phase diagram of bulks and chiral Majorana edge states in nanoribbons. By numerically studying the phase diagram, we found that the non-uniformity of either the superconducting pairing parameters or the exchange field at the two sublattices is necessary to induce a topological superconductor phase with chiral Majorana edge states. The BdG Chern number of certain topological superconductor phases is $\pm 1$ or $\pm 3$, such that the corresponding nanoribbons have one or three pairs of chiral Majorana edge states, respectively.

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References in corpus (13)

• The electronic properties of graphene
• Non-Abelian Anyons and Topological Quantum Computation
• Superconducting proximity effect and Majorana fermions at the surface of a topological insulator
• Classification of topological insulators and superconductors in three spatial dimensions
• Intrinsic and Rashba Spin-orbit Interactions in Graphene Sheets
• Spin-orbit gap of graphene: First-principles calculations
• Colloquium: Majorana Fermions in nuclear, particle and solid-state physics
• Quantum Anomalous Hall Effect in Graphene from Rashba and Exchange Effects
• Quantum Anomalous Hall Effect in Graphene Proximity Coupled to an Antiferromagnetic Insulator
• Magnetic Insulator-Induced Proximity Effects in Graphene: Spin Filtering and Exchange Splitting Gaps
• Giant spin orbit interaction due to rotating magnetic fields in graphene nanoribbons
• Quantized charge transport in chiral Majorana edge modes
• Chiral Majorana Edge Modes and Vortex Majorana Zero Modes in Superconducting Antiferromagnetic Topological Insulator