Faculty Publications

Document Type

Article

Keywords

Magnetic moments, x-ray diffraction, Crystal structure, Antiferromagnetism, Lattice constants

Journal/Book/Conference Title Title

AIP Advances

Volume

7

Issue

5

Abstract

Recent discovery of a new class of materials, spin-gapless semiconductors (SGS), has attracted considerable attention in the last few years, primarily due to potential applications in the emerging field of spin-based electronics (spintronics). Here, we investigate structural, electronic, and magnetic properties of one potential SGS compound, MnCrVAl, using various experimental and theoretical techniques. Our calculations show that this material exhibits ≈ 0.5 eV band gap for the majority-spin states, while for the minority-spin it is nearly gapless. The calculated magnetic moment for the completely ordered structure is 2.9 µB/f.u., which is different from our experimentally measured value of almost zero. This discrepancy is explained by the structural disorder. In particular, A2 type disorder, where Mn or Cr atoms exchange their positions with Al atoms, results in induced antiferromagnetic exchange coupling, which, at a certain level of disorder, effectively reduces the total magnetic moment to zero. This is consistent with our x-ray diffraction measurements which indicate the presence of A2 disorder in all of our samples. In addition, we also show that B2 disorder does not result in antiferromagnetic exchange coupling and therefore does not significantly reduce the total magnetic moment.

Department

Department of Physics

Comments

First published in AIP Advances, v. 7 n. 5 (2016), published by American Institute of Physics. DOI: 10.1063/1.4972797

Original Publication Date

12-19-2016

DOI of published version

10.1063/1.4972797

Repository

UNI ScholarWorks, University of Northern Iowa, Rod Library

Date Digital

2016

Copyright

©2016 P. Kharel, J. Herran, P. Lukashev, Y. Jin, J. Waybright, S. Gilbert, B. Staten, P. Gray, S. Valloppilly, Y. Huh, and D. J. Sellmyer. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Creative Commons License

Creative Commons Attribution 4.0 License
This work is licensed under a Creative Commons Attribution 4.0 License.

Language

EN

File Format

application/pdf

Included in

Physics Commons

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