Intrinsic anharmonic localization in thermoelectric PbSe
Abstract
Lead chalcogenides have exceptional thermoelectric properties and intriguing anharmonic lattice dynamics underlying their low thermal conductivities. An ideal material for thermoelectric efficiency is the phonon glass–electron crystal, which drives research on strategies to scatter or localize phonons while minimally disrupting electronic-transport. Anharmonicity can potentially do both, even in perfect crystals, and simulations suggest that PbSe is anharmonic enough to support intrinsic localized modes that halt transport. Here, we experimentally observe high-temperature localization in PbSe using neutron scattering but find that localization is not limited to isolated modes – zero group velocity develops for a significant section of the transverse optic phonon on heating above a transition in the anharmonic dynamics. Arrest of the optic phonon propagation coincides with unusual sharpening of the longitudinal acoustic mode due to a loss of phase space for scattering. Our study shows how nonlinear physics beyond conventional anharmonic perturbations can fundamentally alter vibrational transport properties.
Additional Information
This is a U.S. government work and not under copyright protection in the U.S.; foreign copyright protection may apply 2019. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. Received 25 October 2018; Accepted 05 April 2019; Published 26 April 2019. Data availability: The data that support the findings of this study are available from the corresponding author on request. The authors thank D. Bansal for assistance in orienting the PbSe crystal. This work was supported by the US Department of Energy, Office of Science, Office of Basic Energy Sciences, Materials Sciences and Engineering Division under Contract Number DE-AC05-00OR22725. A portion of this research performed at the Oak Ridge National Laboratory's Spallation Neutron Source was sponsored by the US Department of Energy, Office of Basic Energy Sciences. The authors acknowledge the support of the National Institute of Standards and Technology, US Department of Commerce, in providing the neutron research facilities used in this work. The identification of any commercial product or trade name does not imply endorsement or recommendation by the National Institute of Standards and Technology. This research used resources of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. H. Wang's effort was sponsored by the DOE Energy Efficiency and Renewable Energy, Office of Vehicle Technologies Materials program. N.S. and A.J.M. acknowledge the support of the DARPA MATRIX program under Grant No. HR0011-15-2-0039. This work used the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by National Science Foundation Grant No. ACI-1053575. Author Contributions: M.E.M. designed the experiments with theoretical guidance from A.J.M., N.S., and O.H. The triple-axis thermal neutron scattering measurements were performed by M.E.M., P.J.S. and J.W.L. The time-of-flight cold neutron scattering measurements were performed by V.O.G., N.S., and M.E.M. The inelastic x-ray scattering measurements were performed by A.A., M.E.M., R.P.H. and J.D.B. The neutron and x-ray scattering data were analyzed by M.E.M. The ab initio simulations were performed by O.H., N.S., and A.J.M. The single crystal growth and Hall effect measurements were performed by A.F.M. and B.C.S. The thermal diffusivity, Seebeck coefficient, and electrical resistivity measurements were performed by H.W. The manuscript was written by M.E.M. with input from all authors. The authors declare no competing interests.Attached Files
Published - s41467-019-09921-4.pdf
Supplemental Material - 41467_2019_9921_MOESM1_ESM.pdf
Supplemental Material - 41467_2019_9921_MOESM2_ESM.pdf
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Additional details
- PMCID
- PMC6486597
- Eprint ID
- 95021
- Resolver ID
- CaltechAUTHORS:20190426-102857516
- Department of Energy (DOE)
- DE-AC05-00OR22725
- Department of Energy (DOE)
- DE-AC02-06CH11357
- Defense Advanced Research Projects Agency (DARPA)
- HR0011-15-2-0039
- NSF
- ACI-1053575
- Created
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2019-04-26Created from EPrint's datestamp field
- Updated
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2021-11-16Created from EPrint's last_modified field