Experimental and density functional study of Mn doped Bi2Te3 topological insulator

DOI: 10.1063/1.4971354

Authors: A. Ghasemi (University of York) , D. Kepaptsoglou (2SuperSTEM Laboratory, SciTech Daresbury Campus) , A. I. Figueroa (Diamond Light Source) , G. A. Naydenov (University of York) , P. J. Hasnip (University of York) , M. I. J. Probert (University of York) , Q. Ramasse (2SuperSTEM Laboratory, SciTech Daresbury Campus) , G. Van Der Laan (Diamond Light Source) , Thorsten Hesjedal (University of Oxford) , V. K. Lazarov (University of York)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Apl Materials , VOL 4

State: Published (Approved)
Published: December 2016
Diamond Proposal Number(s): 9178

Abstract: We present a nanoscale structural and density functional study of the Mn doped 3D topological insulator Bi2Te3. X-ray absorption near edge structure shows that Mn has valency of nominally 2+. Extended x-ray absorption fine structure spectroscopy in combination with electron energy loss spectroscopy (EELS) shows that Mn is a substitutional dopant of Bi and Te and also resides in the van derWaals gap between the quintuple layers of Bi2Te3. Combination of aberration-corrected scanning transmission electron microscopy and EELS shows that Mn substitution of Te occurs in film regions with increased Mn concentration. First-principles calculations show that the Mn dopants favor octahedral sites and are ferromagnetically coupled.

Journal Keywords: topological insulators; EXAFS; TEM

Subject Areas: Physics, Materials, Technique Development

Diamond Offline Facilities: Magnetic Spectroscopy Lab
Instruments: B18-Core EXAFS

Added On: 16/12/2016 12:15

Documents:
1.pdf

Discipline Tags:

Surfaces Quantum Materials Physics Hard condensed matter - structures Materials Science interfaces and thin films

Technical Tags:

Spectroscopy X-ray Absorption Spectroscopy (XAS) Extended X-ray Absorption Fine Structure (EXAFS)