Absence of Magnetic Proximity Effect at the Interface of Bi_{2}Se_{3} and (Bi,Sb)_{2}Te_{3} with EuS

A I Figueroa; F Bonell; M G Cuxart; M Valvidares; P Gargiani; G van der Laan; A Mugarza; S O Valenzuela

doi:10.1103/PhysRevLett.125.226801

Absence of Magnetic Proximity Effect at the Interface of Bi_{2}Se_{3} and (Bi,Sb)_{2}Te_{3} with EuS

Phys Rev Lett. 2020 Nov 27;125(22):226801. doi: 10.1103/PhysRevLett.125.226801.

Authors

A I Figueroa¹, F Bonell¹, M G Cuxart^{1

2}, M Valvidares³, P Gargiani³, G van der Laan⁴, A Mugarza^{1

5}, S O Valenzuela^{1

5}

Affiliations

¹ Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, 08193 Barcelona, Spain.
² Universitat Autònoma de Barcelona (UAB), Bellaterra 08193, Spain.
³ ALBA Synchrotron Light Source, Barcelona 08290, Spain.
⁴ Diamond Light Source, Harwell Science and Innovation Campus, Didcot OX11 0DE, United Kingdom.
⁵ Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona 08010, Spain.

PMID: 33315425
DOI: 10.1103/PhysRevLett.125.226801

Abstract

We performed x-ray magnetic circular dichroism (XMCD) measurements on heterostructures comprising topological insulators (TIs) of the (Bi,Sb)_{2}(Se,Te)_{3} family and the magnetic insulator EuS. XMCD measurements allow us to investigate element-selective magnetic proximity effects at the very TI/EuS interface. A systematic analysis reveals that there is neither significant induced magnetism within the TI nor an enhancement of the Eu magnetic moment at such interface. The induced magnetic moments in Bi, Sb, Te, and Se sites are lower than the estimated detection limit of the XMCD measurements of ∼10^{-3} μ_{B}/at.