f-electron hybridised Fermi surface in magnetic field-induced metallic YbB<inf>12</inf>
Authors
Hartstein, M
Elvin, T
Polyakov, E
Vu, TH
Wichitwechkarn, V
Förster, T
Wosnitza, J
Murphy, TP
Shitsevalova, N
Johannes, MD
Lonzarich, Gilbert
Publication Date
2022-01-21Journal Title
npj Quantum Materials
ISSN
2397-4648
Publisher
Springer Science and Business Media LLC
Volume
7
Issue
1
Language
en
Type
Article
This Version
VoR
Metadata
Show full item recordCitation
Liu, H., Hickey, A., Hartstein, M., Davies, A., Eaton, A., Elvin, T., Polyakov, E., et al. (2022). f-electron hybridised Fermi surface in magnetic field-induced metallic YbB<inf>12</inf>. npj Quantum Materials, 7 (1) https://doi.org/10.1038/s41535-021-00413-7
Description
Funder: EC | EU Framework Programme for Research and Innovation H2020 | H2020 Priority Excellent Science | H2020 European Research Council (H2020 Excellent Science - European Research Council); doi: https://doi.org/10.13039/100010663
Funder: Ministry of Education (Ministry of Education, Republic of China (Taiwan)); doi: https://doi.org/10.13039/100010002
Funder: RCUK | Engineering and Physical Sciences Research Council (EPSRC); doi: https://doi.org/10.13039/501100000266
Funder: RCUK | Economic and Social Research Council (ESRC); doi: https://doi.org/10.13039/501100000269
Funder: Deutsche Forschungsgemeinschaft (German Research Foundation); doi: https://doi.org/10.13039/501100001659
Funder: National Science Foundation (NSF); doi: https://doi.org/10.13039/100000001
Funder: United States Department of Defense | United States Navy | Office of Naval Research (ONR); doi: https://doi.org/10.13039/100000006
Abstract
The nature of the Fermi surface observed in the recently discovered family of
unconventional insulators starting with SmB$_6$ and subsequently YbB$_{12}$ is
a subject of intense inquiry. Here we shed light on this question by comparing
quantum oscillations between the high magnetic field-induced metallic regime in
YbB$_{12}$ and the unconventional insulating regime. In the field-induced
metallic regime beyond 47 T, we find prominent quantum oscillations in the
contactless resistivity characterised by multiple frequencies up to at least
3000 T and heavy effective masses up to at least 17 $m_\text{e}$,
characteristic of an $f$-electron hybridised metallic Fermi surface. The growth
of quantum oscillation amplitude at low temperatures in electrical transport
and magnetic torque in insulating YbB$_{12}$ is closely similar to the
Lifshitz-Kosevich low temperature growth of quantum oscillation amplitude in
field-induced metallic YbB$_{12}$, pointing to an origin of quantum
oscillations in insulating YbB$_{12}$ from in-gap neutral low energy
excitations. The field-induced metallic regime of YbB$_{12}$ is characterised
by more Fermi surface sheets of heavy quasiparticle effective mass that emerge
in addition to the heavy Fermi surface sheets yielding multiple quantum
oscillation frequencies below 1000 T observed in both insulating and metallic
regimes. We thus observe a heavy multi-component Fermi surface in which
$f$-electron hybridisation persists from the unconventional insulating to the
field-induced metallic regime of YbB$_{12}$, which is in distinct contrast to
the unhybridised conduction electron Fermi surface observed in the case of the
unconventional insulator SmB$_6$. Our findings require a different theoretical
model of neutral in-gap low energy excitations in which the $f$-electron
hybridisation is retained in the case of the unconventional insulator
YbB$_{12}$.
Keywords
Article, /639/766/119/995, /639/766/119/2795, article
Sponsorship
European Research Council (337425)
Engineering and Physical Sciences Research Council (EP/M000524/1)
Engineering and Physical Sciences Research Council (EP/M506485/1)
Engineering and Physical Sciences Research Council (EP/P024947/1)
European Research Council (772891)
EPSRC (1805236)
EPSRC (2124504)
Identifiers
s41535-021-00413-7, 413
External DOI: https://doi.org/10.1038/s41535-021-00413-7
This record's URL: https://www.repository.cam.ac.uk/handle/1810/333221
Rights
Licence:
http://creativecommons.org/licenses/by/4.0/
Statistics
Total file downloads (since January 2020). For more information on metrics see the
IRUS guide.