TY - JOUR
T1 - Large Fermi surface in pristine kagome metal CsV3Sb5 and enhanced quasiparticle effective masses
AU - Zhang, Wei
AU - Poon, Tsz Fung
AU - Tsang, Chun Wai
AU - Wang, Wenyan
AU - Liu, X.
AU - Xie, J.
AU - Lam, S. T.
AU - Wang, Shanmin
AU - Lai, Kwing To
AU - Pourret, A.
AU - Seyfarth, G.
AU - Knebel, G.
AU - Yu, Wing Chi
AU - Goh, Swee K.
PY - 2024/5/21
Y1 - 2024/5/21
N2 - The kagome metal CsV3Sb5 is an ideal platform to study the interplay between topology and electron correlation. To understand the fermiology of CsV3Sb5, intensive quantum oscillation (QO) studies at ambient pressure have been conducted. However, due to the Fermi surface reconstruction by the complicated charge density wave (CDW) order, the QO spectrum is exceedingly complex, hindering a complete understanding of the fermiology. Here, we directly map the Fermi surface of the pristine CsV3Sb5 by measuring Shubnikov–de Haas QOs up to 29 T under pressure, where the CDW order is completely suppressed. The QO spectrum of the pristine CsV3Sb5 is significantly simpler than the one in the CDW phase, and the detected oscillation frequencies agree well with our density functional theory calculations. In particular, a frequency as large as 8,200 T is detected. Pressure-dependent QO studies further reveal a weak but noticeable enhancement of the quasiparticle effective masses on approaching the critical pressure where the CDW order disappears, hinting at the presence of quantum fluctuations. Our high-pressure QO results reveal the large, unreconstructed Fermi surface of CsV3Sb5, paving the way to understanding the parent state of this intriguing metal in which the electrons can be organized into different ordered states. © 2024 the Author(s). Published by PNAS.
AB - The kagome metal CsV3Sb5 is an ideal platform to study the interplay between topology and electron correlation. To understand the fermiology of CsV3Sb5, intensive quantum oscillation (QO) studies at ambient pressure have been conducted. However, due to the Fermi surface reconstruction by the complicated charge density wave (CDW) order, the QO spectrum is exceedingly complex, hindering a complete understanding of the fermiology. Here, we directly map the Fermi surface of the pristine CsV3Sb5 by measuring Shubnikov–de Haas QOs up to 29 T under pressure, where the CDW order is completely suppressed. The QO spectrum of the pristine CsV3Sb5 is significantly simpler than the one in the CDW phase, and the detected oscillation frequencies agree well with our density functional theory calculations. In particular, a frequency as large as 8,200 T is detected. Pressure-dependent QO studies further reveal a weak but noticeable enhancement of the quasiparticle effective masses on approaching the critical pressure where the CDW order disappears, hinting at the presence of quantum fluctuations. Our high-pressure QO results reveal the large, unreconstructed Fermi surface of CsV3Sb5, paving the way to understanding the parent state of this intriguing metal in which the electrons can be organized into different ordered states. © 2024 the Author(s). Published by PNAS.
KW - CDW quantum phase transition
KW - kagome metal
KW - pristine CsV3Sb5
KW - quantum oscillations
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UR - https://www.scopus.com/record/pubmetrics.uri?eid=2-s2.0-85193493078&origin=recordpage
U2 - 10.1073/pnas.2322270121
DO - 10.1073/pnas.2322270121
M3 - RGC 21 - Publication in refereed journal
C2 - 38753515
SN - 0027-8424
VL - 121
JO - PNAS: Proceedings of the National Academy of Sciences of the United States of America
JF - PNAS: Proceedings of the National Academy of Sciences of the United States of America
IS - 21
M1 - e2322270121
ER -