Towards microscopic control of the magnetic exchange coupling at the surface of a topological insulator
Rüssmann, Philipp (Peter Grünberg Institut)
Mahatha, Sanjoy K. (Aarhus University. Department of Physics and Astronomy)
Sessi, Paolo (Universität Würzburg)
Valbuena, Miguel Ángel (Institut Català de Nanociència i Nanotecnologia)
Bathon, Thomas (Universität Würzburg)
Fauth, Kai (Universität Würzburg)
Godey, Sylvie (Institut Català de Nanociència i Nanotecnologia)
Mugarza, Aitor (Institut Català de Nanociència i Nanotecnologia)
Kokh, Konstantin A. (Novosibirsk State University)
Tereshchenko, Oleg E. (Novosibirsk State University)
Gargiani, Pierluigi (ALBA Laboratori de Llum de Sincrotró)
Valvidares, Manuel (ALBA Laboratori de Llum de Sincrotró)
Jiménez, Erika (European Synchrotron Radiation Facility)
Brookes, N. B (European Synchrotron Radiation Facility)
Bode, Matthias (Universität Würzburg)
Bihlmayer, G (Peter Grünberg Institut)
Blügel, Stefan (Peter Grünberg Institut)
Mavropoulos, Phivos (Peter Grünberg Institut)
Carbone, Carlo (Istituto di Struttura della Materia)
Barla, Alessandro (Istituto di Struttura della Materia)

Date:	2018
Abstract:	Magnetically doped topological insulators may produce novel states of electronic matter, where for instance the quantum anomalous Hall effect state can be realized. Pivotal to this goal is a microscopic control over the magnetic state, defined by the local electronic structure of the dopants and their interactions. We report on the magnetic coupling among Mn or Co atoms adsorbed on the surface of the topological insulator Bi2Te3. Our findings uncover the mechanisms of the exchange coupling between magnetic atoms coupled to the topological surface state in strong topological insulators. The combination of x-ray magnetic circular dichroism and ab initio calculations reveals that the sign of the magnetic coupling at short adatom-adatom distances is opposite for Mn with respect to Co. For both elements, the magnetic exchange reverses its sign at a critical distance between magnetic adatoms, as a result of the interplay between superexchange, double exchange and Ruderman-Kittel-Kasuya-Yoshida interactions.
Grants:	Ministerio de Economía y Competitividad MAT2016-78293-C6-2-R Ministerio de Economía y Competitividad SEV-2013-0295 European Commission 312284
Rights:	Aquest document està subjecte a una llicència d'ús Creative Commons. Es permet la reproducció total o parcial, la distribució, la comunicació pública de l'obra i la creació d'obres derivades, fins i tot amb finalitats comercials, sempre i quan es reconegui l'autoria de l'obra original.
Language:	Anglès
Document:	Article ; recerca ; Versió publicada
Subject:	Magnetic exchange interaction ; Topological insulators ; X-ray magnetic circular dichroism (XMCD) ; Density functional theory (DFT) ; Ruderman-Kittel-Kasuya-Yoshida (RKKY) interaction ; Quantum anomalous Hall effect
Published in:	JPhys materials, Vol. 1, Núm. 1 (September 2018) , art. 015002, ISSN 2515-7639

DOI: 10.1088/2515-7639/aad02a

14 p, 1.8 MB

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Research literature > UAB research groups literature > Research Centres and Groups (research output) > Experimental sciences > Catalan Institute of Nanoscience and Nanotechnology (ICN2)
Research literature > UAB research groups literature > Research Centres and Groups (research output) > Experimental sciences > The ALBA Synchrotron
Articles > Research articles
Articles > Published articles