Inducing magnetism onto the surface of a topological crystalline insulator

Abstract

Inducing magnetism onto a topological crystalline insulator (TCI) has been predicted to result in several novel quantum electromagnetic effects. This is a consequence of the highly strain-sensitive band topology of such symmetry-protected systems. We thus show that placing the TCI surface of SnTe in proximity to EuS, a ferromagnetic insulator, induces magnetism at the interface between SnTe and EuS and thus breaks time-reversal-symmetry in the TCI. Magnetotransport experiments on SnTe-EuS-SnTe trilayer devices reveal a hysteretic lowering of the resistance at the TCI surface that coincides with an increase in the density of magnetic domain walls. This additional conduction could be a signature of topologically-protected surface states within domain walls. Additionally, a hysteretic anomalous Hall effect reveals that the usual in-plane magnetic moment of the EuS layer is canted towards a perpendicular direction at the interface. These results are evidence of induced magnetism at the SnTe-EuS interfaces resulting in broken time-reversal symmetry in the TCI.

Accepted for publication in Physical Review B

References in corpus (6)

• Topological Field Theory of Time-Reversal Invariant Insulators
• Quantized Anomalous Hall Effect in Magnetic Topological Insulators
• Electrically detected interferometry of Majorana fermions in a topological insulator
• Surface quantized anomalous Hall current and magneto-electric effect in magnetically disordered topological insulators
• Quantum Coherent Transport in SnTe Topological Crystalline Insulator Thin Films
• Interlayer coupling in EuS/SrS, EuS/PbSe and EuS/PbTe magnetic semiconductor superlatices

Cited by in corpus (1)

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