TY - JOUR
T1 - Investigation of Planckian behavior in a high-conductivity oxide
T2 - PdCrO2
AU - Zhakina, Elina
AU - Daou, Ramzy
AU - Maignan, Antoine
AU - McGuinness, Philippa H.
AU - König, Markus
AU - Rosner, Helge
AU - Kim, Seo-Jin
AU - Khim, Seunghyun
AU - Grasset, Romain
AU - Konczykowski, Marcin
AU - Tulipman, Evyatar
AU - Mendez-Valderrama, Juan Felipe
AU - Chowdhury, Debanjan
AU - Berg, Erez
AU - Mackenzie, Andrew P.
N1 - Funding: JFMV and DC are supported by faculty startup grants at Cornell University. ET and EB were supported by the European Research Council (ERC) under grant HQMAT (Grant Agreement No. 817799), the Israel-US Binational Science Foundation (BSF), and the Minerva Foundation.
PY - 2023/9/5
Y1 - 2023/9/5
N2 - The layered delafossite metal PdCrO2 is a natural heterostructure ofhighly conductive Pd layers Kondo coupled to localized spins in the adjacent Mott insulating CrO2 layers. At high temperatures T it has a T-linearresistivity which is not seen in the isostructural but non-magnetic PdCoO2.The strength of the Kondo coupling is known, as-grown crystals are extremelyhigh purity and the Fermi surface is both very simple and experimentally known. It is therefore an ideal material platform in which to investigate 'Planckianmetal' physics. We do this by means of controlled introduction of point disorder, measurement of the thermal conductivity and Lorenz ratio and studying the sources of its high temperature entropy. The T-linear resistivity is seen to be due mainly to elastic scattering and to arise from a sum of several scattering mechanisms. Remarkably, this sum leads to a scattering rate within 10% of the Planckian value of kBT/ℏ.
AB - The layered delafossite metal PdCrO2 is a natural heterostructure ofhighly conductive Pd layers Kondo coupled to localized spins in the adjacent Mott insulating CrO2 layers. At high temperatures T it has a T-linearresistivity which is not seen in the isostructural but non-magnetic PdCoO2.The strength of the Kondo coupling is known, as-grown crystals are extremelyhigh purity and the Fermi surface is both very simple and experimentally known. It is therefore an ideal material platform in which to investigate 'Planckianmetal' physics. We do this by means of controlled introduction of point disorder, measurement of the thermal conductivity and Lorenz ratio and studying the sources of its high temperature entropy. The T-linear resistivity is seen to be due mainly to elastic scattering and to arise from a sum of several scattering mechanisms. Remarkably, this sum leads to a scattering rate within 10% of the Planckian value of kBT/ℏ.
U2 - 10.1073/pnas.2307334120
DO - 10.1073/pnas.2307334120
M3 - Editorial
SN - 0027-8424
VL - 120
JO - Proceedings of the National Academy of Sciences
JF - Proceedings of the National Academy of Sciences
IS - 36
M1 - e2307334120
ER -