Do topology and ferromagnetism cooperate at the EuS/Bi${}_2$Se${}_3$ interface?

Abstract

We probe the local magnetic properties of interfaces between the insulating ferromagnet EuS and the topological insulator Bi${}_2$Se${}_3$ using low energy muon spin rotation (LE-$\mu$SR). We compare these to the interface between EuS and the topologically trivial metal, titanium. Below the magnetic transition of EuS, we detect strong local magnetic fields which extend several nm into the adjacent layer and cause a complete depolarization of the muons. However, in both Bi${}_2$Se${}_3$ and titanium we measure similar local magnetic fields, implying that their origin is mostly independent of the topological properties of the interface electronic states. In addition, we use resonant soft X-ray angle resolved photoemission spectroscopy (SX-ARPES) to probe the electronic band structure at the interface between EuS and Bi${}_2$Se${}_3$. By tuning the photon energy to the Eu anti-resonance at the Eu $M_5$ pre-edge we are able to detect the Bi${}_2$Se${}_3$ conduction band, through a protective Al${}_2$O${}_3$ capping layer and the EuS layer. Moreover, we observe a signature of an interface-induced modification of the buried Bi${}_2$Se${}_3$ wave functions and/or the presence of interface states.

References in corpus (11)

• Topological Field Theory of Time-Reversal Invariant Insulators
• Quantized Anomalous Hall Effect in Magnetic Topological Insulators
• High-precision realization of robust quantum anomalous Hall state in a hard ferromagnetic topological insulator
• Imaging Dirac-Mass Disorder from Magnetic Dopant-Atoms in the Ferromagnetic Topological Insulator Cr${}_x$(Bi${}_{0.1}$Sb${}_{0.9}$)${}_{2-x}$Te${}_3$
• Above 400 K Robust Perpendicular Ferromagnetic Phase in a Topological Insulator
• Large-gap magnetic topological heterostructure formed by subsurface incorporation of a ferromagnetic layer
• Magnetic proximity effect at Bi${}_2$Se${}_3$/EuS interface with broken inversion symmetry
• Spectroscopic perspective on the interplay between electronic and magnetic properties of magnetically doped topological insulators
• Formation of hydrogen impurity states in silicon and insulators at low implantation energies
• Dirac-Electrons-Mediated Magnetic Proximity Effect in Topological Insulator / Magnetic Insulator Heterostructures
• Inducing magnetism onto the surface of a topological crystalline insulator

Cited by in corpus (8)

• Van der Waals heterostructures for spintronics and opto-spintronics
• Progress and prospects in the quantum anomalous Hall effect
• Absence of magnetic-proximity effect at the interface of Bi${}_2$Se${}_3$ and (Bi,Sb)${}_2$Te${}_3$ with EuS
• Science Case for the new High-Intensity Muon Beams HIMB at PSI
• Partial Charge Transfer and Absence of Induced Magnetization in EuS(111)/Bi${}_2$Se${}_3$ Heterostructures
• Surface-Localized Magnetic Order in RuO2 Thin Films Revealed by Low-Energy Muon Probes
• Discovery of a high-temperature antiferromagnetic state and transport signatures of exchange interactions in a Bi2Se3/EuSe heterostructure
• Interface-Induced Stability of Nontrivial Topological Spin Textures: Unveiling Room-Temperature Hopfions and Skyrmions