Magnetoelastic hybrid excitations in CeAuAl3
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F19%3A10398913" target="_blank" >RIV/00216208:11320/19:10398913 - isvavai.cz</a>
Result on the web
<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=MviIiKh_jW" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=MviIiKh_jW</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1073/pnas.1819664116" target="_blank" >10.1073/pnas.1819664116</a>
Alternative languages
Result language
angličtina
Original language name
Magnetoelastic hybrid excitations in CeAuAl3
Original language description
Nearly a century of research has established the Born-Oppenheimer approximation as a cornerstone of condensed-matter systems, stating that the motion of the atomic nuclei and electrons may be treated separately. Interactions beyond the Born- Oppenheimer approximation are at the heart of magneto-elastic functionalities and instabilities. We report comprehensive neutron spectroscopy and ab initio phonon calculations of the coupling between phonons, CEF-split localized 4f electron states, and conduction electrons in the paramagnetic regime of CeAuAl3, an archetypal Kondo lattice compound. We identify two distinct magneto-elastic hybrid excitations that form even though all coupling constants are small. First, we find a CEF-phonon bound state reminiscent of the vibronic bound state (VBS) observed in other materials. However, in contrast to an abundance of optical phonons, so far believed to be essential for a VBS, the VBS in CeAuAl3 arises from a comparatively low density of states of acoustic phonons. Second, we find a pronounced anticrossing of the CEF excitations with acoustic phonons at zero magnetic field not observed before. Remarkably, both magneto-elastic excitations are well developed despite considerable damping of the CEFs that arises dominantly by the conduction electrons. Taking together the weak coupling with the simultaneous existence of a distinct VBS and anticrossing in the same material in the presence of damping suggests strongly that similarly well-developed magneto-elastic hybrid excitations must be abundant in a wide range of materials. In turn, our study of the excitation spectra of CeAuAl3 identifies a tractable point of reference in the search for magneto-elastic functionalities and instabilities.
Czech name
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Czech description
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Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
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OECD FORD branch
10302 - Condensed matter physics (including formerly solid state physics, supercond.)
Result continuities
Project
<a href="/en/project/GC17-04925J" target="_blank" >GC17-04925J: Multi-Component Electronic Correlations in Non-Centrosymmetric f-Electron Compounds</a><br>
Continuities
P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)
Others
Publication year
2019
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Proceedings of the National Academy of Sciences of the United States of America
ISSN
0027-8424
e-ISSN
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Volume of the periodical
116
Issue of the periodical within the volume
14
Country of publishing house
US - UNITED STATES
Number of pages
6
Pages from-to
6695-6700
UT code for WoS article
000463069900036
EID of the result in the Scopus database
2-s2.0-85064044122