Induced anisotropic superconductivity in the intrinsic magnetic topological insulator MnBi₂Te₄

Abstract Integrating superconducting order into magnetic topological insulators (MTIs) has garnered significant attention for its potential to realize exotic phases, such as chiral Majorana edge modes. In this study, we investigate the proximity-induced superconducting correlations on MTI MnBi 2 Te 4 by proximitizing it with the s -wave superconductor NbSe 2 and conducting low-temperature electrical transport measurements. A distinct negative cusp-like magnetoresistance (MR) is observed within a narrow range of out-of-plane magnetic fields, while hysteretic negative MR is detected when the magnetic field is applied in-plane. Differential conductance measurements performed at low temperatures reveal a sharp V-shaped zero-bias dip with distinct ripples, both of which diminish with increasing temperature. These ripples are further suppressed by the application of small out-of-plane magnetic fields. Additionally, signatures of superconducting correlations are observed in regions of MnBi 2 Te 4 away from the MnBi 2 Te 4 /NbSe 2 interface, which evolves with temperature and magnetic field. These findings provide valuable insights into the anisotropic nature of induced superconductivity in MTIs.