How disorder affects topological surface states in the limit of ultrathin Bi2Se3 films
Song, Kenan (Institut Català de Nanociència i Nanotecnologia)
Robles, Roberto (Institut Català de Nanociència i Nanotecnologia)
Soriano, David (Institut Català de Nanociència i Nanotecnologia)
Ordejon, Pablo (Institut Català de Nanociència i Nanotecnologia)
Roche, Stephan (Institut Català de Nanociència i Nanotecnologia)

Date:	2016
Abstract:	We present a first-principles study of electronic properties of ultrathin films of topological insulators (TIs) and scrutinize the role of disorder on the robustness of topological surface states, which can be analysed through their spin textures. The presence of twin grain boundaries is found to increase the band gap of the film, while preserving the spin texture of states in first conduction and valence bands. Differently, partial hydrogenation of one surface not only results in some self-doping effect, but also provokes some alteration of the spin texture symmetry of the electronic states. The formation of a new Dirac cone at M-point of the Brillouin zone of the hydrogenated surface, together with a modified spin texture characteristics are consistent with a dominant Dresselhaus spin-orbit interaction type, more usually observed in 3D materials. Our findings indicate that defects can either be detrimental or beneficial for exploring spin transport of surface states in the limit of ultrathin films of TIs, which maximizes surface over bulk phenomena.
Grants:	Ministerio de Economía y Competitividad FIS2015-67767-P Ministerio de Economía y Competitividad SEV-2013-0295
Rights:	Tots els drets reservats.
Language:	Anglès
Document:	Article ; recerca ; Versió publicada
Published in:	2D Materials, Vol. 3, Núm. 4 (December 2016) , art. 045007, ISSN 2053-1583

DOI: 10.1088/2053-1583/3/4/045007

Post-print 12 p, 6.0 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)
Articles > Research articles
Articles > Published articles