Real-space visualization of short-range antiferromagnetic correlations in a magnetically enhanced thermoelectric

Raju Baral; Jacob A. Christensen; Parker K. Hamilton; Feng Ye; Karine Chesnel; Taylor D. Sparks; Rosa Ward; Jiaqiang Yan; Michael A. McGuire; Michael E. Manley; Julie B. Staunton; Raphaël P. Hermann; Benjamin A. Frandsen

doi:10.1016/j.matt.2022.03.011

Real-space visualization of short-range antiferromagnetic correlations in a magnetically enhanced thermoelectric

Raju Baral, Jacob A. Christensen, Parker K. Hamilton, Feng Ye, Karine Chesnel, Taylor D. Sparks, Rosa Ward, Jiaqiang Yan, Michael A. McGuire, Michael E. Manley, Julie B. Staunton, Raphaël P. Hermann, Benjamin A. Frandsen

Research output: Contribution to journal › Article › peer-review

18 Scopus citations

Abstract

Short-range magnetic correlations can significantly increase the thermopower of magnetic semiconductors, representing a noteworthy development in the decades-long effort to develop high-performance thermoelectric materials. Here, we reveal the nature of the thermopower-enhancing magnetic correlations in the antiferromagnetic semiconductor MnTe. Using magnetic pair distribution function analysis of neutron-scattering data, we obtain a detailed, real-space view of robust, nanometer-scale, antiferromagnetic correlations that persist into the paramagnetic phase above the Néel temperature T_N = 307 K. The magnetic correlation length in the paramagnetic state is significantly longer along the crystallographic c axis than within the ab plane, pointing to anisotropic magnetic interactions. Ab initio calculations of the spin-spin correlations using density functional theory in the disordered local moment approach reproduce this result with quantitative accuracy. These findings constitute the first real-space picture of short-range spin correlations in a magnetically enhanced thermoelectric and inform future efforts to optimize thermoelectric performance by magnetic means.

Original language	English
Pages (from-to)	1853-1864
Number of pages	12
Journal	Matter
Volume	5
Issue number	6
DOIs	https://doi.org/10.1016/j.matt.2022.03.011
State	Published - Jun 1 2022

Funding

We thank Michelle Everett, Jue Liu, and Jörg Neuefeind for their support at the NOMAD beamline and James Torres for assistance during the CORELLI beamtime at ORNL . We thank an anonymous referee for suggesting that we consider the possibility of an anisotropic thermopower. Work by R.B., P.H., and B.A.F. was supported by the U.S. Department of Energy , Office of Science , Office of Basic Energy Science through Award No. DE-SC0021134 . J.C. acknowledges support from the College of Physical and Mathematical Sciences at Brigham Young University . Work by J.B.S. was supported by the UK Engineering and Physical Sciences Research Council , grant no. EP/M028941/1 . Work at ORNL by J.Y. and M.A.M. (synthesis and magnetometry) and by M.E.M. and R.P.H. (neutron scattering) was supported by the US Department of Energy, Office of Science, Office of Basic Energy Science, Materials Science and Engineering Division. T.D.S. and R.W. acknowledge support from the US National Science Foundation CAREER program under grant no. DMR-1651668. This study used resources at the Spallation Neutron Source ( SNS ), a DOE Office of Science User Facility operated by the Oak Ridge National Laboratory .

Funders	Funder number
College of Physical and Mathematical Sciences at Brigham Young University
National Science Foundation	DMR-1651668
U.S. Department of Energy
Office of Science
Basic Energy Sciences	DE-SC0021134
Oak Ridge National Laboratory
Division of Materials Sciences and Engineering
Engineering and Physical Sciences Research Council	EP/M028941/1

Keywords

MAP2: Benchmark
MnTe
antiferromagnetic semiconductor
magnetic correlations
magnetic pair distribution function
neutron scattering
pair distribution function
paramagnon drag
thermoelectric

Access to Document

10.1016/j.matt.2022.03.011

Cite this

Baral, R., Christensen, J. A., Hamilton, P. K., Ye, F., Chesnel, K., Sparks, T. D., Ward, R., Yan, J., McGuire, M. A., Manley, M. E., Staunton, J. B., Hermann, R. P., & Frandsen, B. A. (2022). Real-space visualization of short-range antiferromagnetic correlations in a magnetically enhanced thermoelectric. Matter, 5(6), 1853-1864. https://doi.org/10.1016/j.matt.2022.03.011

@article{6c02a45540ed409aab147a2714b47dce,

title = "Real-space visualization of short-range antiferromagnetic correlations in a magnetically enhanced thermoelectric",

abstract = "Short-range magnetic correlations can significantly increase the thermopower of magnetic semiconductors, representing a noteworthy development in the decades-long effort to develop high-performance thermoelectric materials. Here, we reveal the nature of the thermopower-enhancing magnetic correlations in the antiferromagnetic semiconductor MnTe. Using magnetic pair distribution function analysis of neutron-scattering data, we obtain a detailed, real-space view of robust, nanometer-scale, antiferromagnetic correlations that persist into the paramagnetic phase above the N{\'e}el temperature TN = 307 K. The magnetic correlation length in the paramagnetic state is significantly longer along the crystallographic c axis than within the ab plane, pointing to anisotropic magnetic interactions. Ab initio calculations of the spin-spin correlations using density functional theory in the disordered local moment approach reproduce this result with quantitative accuracy. These findings constitute the first real-space picture of short-range spin correlations in a magnetically enhanced thermoelectric and inform future efforts to optimize thermoelectric performance by magnetic means.",

keywords = "MAP2: Benchmark, MnTe, antiferromagnetic semiconductor, magnetic correlations, magnetic pair distribution function, neutron scattering, pair distribution function, paramagnon drag, thermoelectric",

author = "Raju Baral and Christensen, {Jacob A.} and Hamilton, {Parker K.} and Feng Ye and Karine Chesnel and Sparks, {Taylor D.} and Rosa Ward and Jiaqiang Yan and McGuire, {Michael A.} and Manley, {Michael E.} and Staunton, {Julie B.} and Hermann, {Rapha{\"e}l P.} and Frandsen, {Benjamin A.}",

note = "Publisher Copyright: {\textcopyright} 2022 Elsevier Inc.",

year = "2022",

month = jun,

day = "1",

doi = "10.1016/j.matt.2022.03.011",

language = "English",

volume = "5",

pages = "1853--1864",

journal = "Matter",

issn = "2590-2393",

publisher = "Cell Press",

number = "6",

}

TY - JOUR

T1 - Real-space visualization of short-range antiferromagnetic correlations in a magnetically enhanced thermoelectric

AU - Baral, Raju

AU - Christensen, Jacob A.

AU - Hamilton, Parker K.

AU - Ye, Feng

AU - Chesnel, Karine

AU - Sparks, Taylor D.

AU - Ward, Rosa

AU - Yan, Jiaqiang

AU - McGuire, Michael A.

AU - Manley, Michael E.

AU - Staunton, Julie B.

AU - Hermann, Raphaël P.

AU - Frandsen, Benjamin A.

PY - 2022/6/1

Y1 - 2022/6/1

N2 - Short-range magnetic correlations can significantly increase the thermopower of magnetic semiconductors, representing a noteworthy development in the decades-long effort to develop high-performance thermoelectric materials. Here, we reveal the nature of the thermopower-enhancing magnetic correlations in the antiferromagnetic semiconductor MnTe. Using magnetic pair distribution function analysis of neutron-scattering data, we obtain a detailed, real-space view of robust, nanometer-scale, antiferromagnetic correlations that persist into the paramagnetic phase above the Néel temperature TN = 307 K. The magnetic correlation length in the paramagnetic state is significantly longer along the crystallographic c axis than within the ab plane, pointing to anisotropic magnetic interactions. Ab initio calculations of the spin-spin correlations using density functional theory in the disordered local moment approach reproduce this result with quantitative accuracy. These findings constitute the first real-space picture of short-range spin correlations in a magnetically enhanced thermoelectric and inform future efforts to optimize thermoelectric performance by magnetic means.

AB - Short-range magnetic correlations can significantly increase the thermopower of magnetic semiconductors, representing a noteworthy development in the decades-long effort to develop high-performance thermoelectric materials. Here, we reveal the nature of the thermopower-enhancing magnetic correlations in the antiferromagnetic semiconductor MnTe. Using magnetic pair distribution function analysis of neutron-scattering data, we obtain a detailed, real-space view of robust, nanometer-scale, antiferromagnetic correlations that persist into the paramagnetic phase above the Néel temperature TN = 307 K. The magnetic correlation length in the paramagnetic state is significantly longer along the crystallographic c axis than within the ab plane, pointing to anisotropic magnetic interactions. Ab initio calculations of the spin-spin correlations using density functional theory in the disordered local moment approach reproduce this result with quantitative accuracy. These findings constitute the first real-space picture of short-range spin correlations in a magnetically enhanced thermoelectric and inform future efforts to optimize thermoelectric performance by magnetic means.

KW - MAP2: Benchmark

KW - MnTe

KW - antiferromagnetic semiconductor

KW - magnetic correlations

KW - magnetic pair distribution function

KW - neutron scattering

KW - pair distribution function

KW - paramagnon drag

KW - thermoelectric

UR - http://www.scopus.com/inward/record.url?scp=85132395427&partnerID=8YFLogxK

U2 - 10.1016/j.matt.2022.03.011

DO - 10.1016/j.matt.2022.03.011

M3 - Article

AN - SCOPUS:85132395427

SN - 2590-2393

VL - 5

SP - 1853

EP - 1864

JO - Matter

JF - Matter

IS - 6

ER -

Real-space visualization of short-range antiferromagnetic correlations in a magnetically enhanced thermoelectric

Abstract

Funding

Keywords

Access to Document

Other files and links

Fingerprint

Cite this