Publication: The origin of anisotropy and high density of states in the electronic structure of Cr2GeC by means of polarized soft X-ray spectroscopy and ab initio calculations
Loading...
Official URL
Full text at PDC
Publication Date
2015-09-28
Authors
Advisors (or tutors)
Editors
Journal Title
Journal ISSN
Volume Title
Publisher
IOPScience
Citations
Exportar
Abstract
The anisotropy in the electronic structure of the inherently nanolaminated ternary phase Cr2GeC is investigated by bulk-sensitive and element selective soft x-ray absorption/emission spectroscopy. The angle-resolved absorption/emission measurements reveal differences between the in-plane and out-of-plane bonding at the (0001) interfaces of Cr2GeC. The Cr L 2, 3, C K, and Ge M 1, M 2, 3 emission spectra are interpreted with first-principles density-functional theory (DFT) including core-to-valence dipole transition matrix elements. For the Ge 4s states, the x-ray emission measurements reveal two orders of magnitude higher intensity at the Fermi level than DFT within the General Gradient Approximation (GGA) predicts. We provide direct evidence of anisotropy in the electronic structure and the orbital occupation that should affect the thermal expansion coefficient and transport properties. As shown in this work, hybridization and redistribution of intensity from the shallow 3d core levels to the 4s valence band explain the large Ge density of states at the Fermi level.
Description
© 2015 IOP Publishing Ltd.
We thank the staff at MAX IV Laboratory for experimental support as well as M Jaouen and V Mauchamp for discussions. This work was financially supported by the Swedish Research Council Linnaeus Grant LiLi-NFM and the Swedish Foundation for Strategic Research (SSF) through the Synergy Grant FUNCASE and Future Research Leaders 5 Program. PE also acknowledges the University of Poitiers for a Visiting. Professor position. M Mattesini acknowledges financial support by the Spanish Ministry of Economy and Competitiveness (CGL 2013-41860-P) and by the BBVA Foundation.
UCM subjects
Unesco subjects
Keywords
Citation
[1] Wang J and Zhou Y 2009 Annu. Rev. Mater. Res. 39 415–43
[2] Eklund P, Beckers M, Jansson U, Höberg H and Hultman L 2010 Thin Solid Films 518 1851–78
[3] Barsoum M W 2000 Prog. Solid State Chem. 28 201–81
[4] Jeitschko W et al 1963 Monatshefte Chem. 94 844
[5] Bouhemadou A 2009 Appl. Phys. A 96 959
[6] Scabarozi T H et al 2009 J. Appl. Phys. 105 013543
[7] Cabioch T, Eklund P, Mauchamp V, Jaouen M and Barsoum M W 2013 J. Eur. Ceram. Soc. 33 897
[8] Lane N J, Vogel S and Barsoum M W 2011 J. Am. Ceram. Soc. 94 3473
[9] Zhou W, Liu L and Wu P 2009 J. Appl. Phys. 106 033501
[10] Ramzan M, Lebègue S and Ahuja R 2011 Phys. Status Solidi 5 122
[11] Ramzan M, Lebegue S and Ahuja R 2012 Solid State Commun. 152 1147
[12] Mattesini M and Magnuson M 2013 J. Phys.: Condens. Matter 25 035601
[13] Dahlqvist M, Alling B and Rosen J 2013 J. Appl. Phys. 113 216103
[14] Jaouen M, Bugnet M, Jaouen N, Ohresser P, Mauchamp V, Cabioc’h T and Rogalev A 2014 J. Phys.: Condens. Matter 26 176002
[15] Barsoum M, Scabarozi T H, Amini S, Hettinger J D and Lofland S E 2011 J. Am. Ceram. Soc. 94 4123
[16] Drulis M K, Drulis H, Hackemer A E, Leaffer O, Spanier J, Amini S, Barsoum M W, Guilbert T and El-Raghy T 2008 J. Appl. Phys. 104 023526
[17] Magnuson M, Mattesini M, Li S, Höglund C, Beckers M, Hultman L and Eriksson O 2007 Phys. Rev. B 76 195127
[18] Magnuson M, Wilhelmsson O, Palmquist J-P, Jansson U, Mattesini M, Li S, Ahuja R and Eriksson O 2006 Phys. Rev. B 74 195108
[19] Magnuson M, Mattesini M, Wilhelmsson O, Emmerlich J, Palmquist J-P, Li S, Ahuja R, Hultman L, Eriksson O and Jansson U 2006 Phys. Rev. B 74 205102
[20] Eklund P, Bugnet M, Mauchamp V, Dubois S, Tromas C, Jensen J, Piraux L, Gence L, Jaouen M and Cabioh T 2011 Phys. Rev. B 84 075424
[21] Magnuson M, Mattesini M, Höglund C, Abrikosov I A, Birch J and Hultman L 2008 Phys. Rev. B 78 235102 [22] Magnuson M, Lewin E, Hultman U and Jansson U 2009 Phys. Rev. B 80 235108
[23] Klementev K V 2001 J. Phys. D: Appl. Phys. 34 209–17 (Klementiev K V XANES dactyloscope for Windows, freeware: www.desy.de/~klmn/xanda.html www.cells.es/ old/Beamlines/CLAESS/software/)
[24] Magnuson M, Wassdahl N and Nordgren J 1997 Phys. Rev. B 56 12238
[25] Kohn W and Sham L J 1965 Phys. Rev. 140 A1133–8
[26] von Barth U and Grossmann G 1982 Phys. Rev. B 25 5150 79
[27] Blaha P, Schwarz K, Madsen G K H, Kvasnicka D and Luitz J 2001 WIEN2K An Augmented Plane Wave + Local Orbitals Program for Calculating Crystal (Properties) (Wien: Karlheinz Schwarz, Techn. Universität Wien, Austria)
[28] Perdew J P, Burke S and Ernzerhof M 1996 Phys. Rev. Lett. 77 3865
[29] Magnuson M, Butorin S M, Såthe C, Nordgren J and Ravindran P 2004 Europhys. Lett. 68 289
[30] Baroni S, de Gironcoli S, Dal Corso A and Giannozzi P 2001 Rev. Mod. Phys. 73 515
[31] Giannozzi P et al 2009 J. Phys. Condens. Matter 21 395502
[32] Isaev E, QHA project, http://qe-forge.org/qha (nd)
[33] Vanderbilt D 1990 Phys. Rev. B 41 7892
[34] Monkhorst H J and Pack J D 1976 Phys. Rev. B 13 5188
[35] Laskowski R and Blaha P 2010 Phys. Rev. B 82 205104–10
[36] Bugnet M, Jaouen M, Mauchamp V, Cabioc’h T and Hug G 2014 Phys. Rev. B 90 195116
[37] Magnuson M et al 2005 Phys. Rev. B 72 245101–10
[38] Magnuson M, Wilhelmsson O, Mattesini M, Li S, Ahuja R, Eriksson O, Högberg H, Hultman L and Jansson U 2008 Phys. Rev. B 78 035117
[39] Magnuson M, Mattesini M, Höglund C, Birch J and Hultman L 2010 Phys. Rev. B 81 085125
[40] Kawai J, Nakajima K and Gohshi Y 1993 Spectrochim. Acta B 48 1281
[41] Magnuson M, Duda L-C, Butorin S M, Kuiper P and Nordgren J 2006 Phys. Rev. B 74 172409
[42] Leaffer O D, Gupta S, Barsoum M W and Spaniera J E 2007 J. Mater. Res. 22 2651
[43] Spanier J E, Gupta S, Amer M and Barsoum M W 2005 Phys. Rev. B 71 012103
[44] Magnuson M, Mattesini M, Van Nong N, Eklund P and Hultman L 2012 Phys. Rev. B 85 195134
[45] Amini S, Zhou A, Gupta S, DeVillier A, Finkel P and Barsoum M W 2008 J. Mater. Res. 23 2157
[46] Li Y F, Gao Y M, Xiao B, Min T, Yang Y, Ma S and Yi D W 2011 J. Alloys Compd. 509 5242
[47] Togo A, Chaput L, Tanaka I and Hug G 2010 Phys. Rev. B 81 174301