The renewed interest in the physics of high Tc superconducting cuprates is being driven by the observation of a rich phenomenology encompassing charge density waves and charge density fluctuations [1]. These excitations are potential vectors for substantial interplay with the lattice degrees of freedom such as phonons or strain [2,3,4].

New theoretical proposals [5,6] and experimental evidence [4] are explicitly connecting these phenomena to the transport properties of the pseudogap and strange metal phases, shedding new light on the nature of the intricate “normal” state of cuprates, and on the causality hierarchy among pseudogap, charge orders and strange metal phenomenology encountered in these fascinating materials [7].

In this minicolloquium, recent experimental observations and theoretical insights, both on the charge density instability and on transport, including the Planckian regime in the overdoped region [8], will be presented and confronted [9]. The interpretation of experimental findings is boosting a lively debate in the community and this event will be an occasion for exposing this discussion to a broader audience. Beyond the large fall out on the superconductivity of cuprates, this session is of interest for the community of quantum materials at large, due to the enormous relevance of understanding the violation of Fermi-liquid Landau theory by the metallic behaviour of various other systems, such as graphene, heavy fermions, ruthenates and Fe pnictides.

References

[1] R. Arpaia et al. Science 365, 906 (2019)

[2] W. S. Lee et al. Nat. Phys. 17 53 (2020)

[3] H. H. Kim et al. Science 362, 1040 (2018)

[4] E. Wahlberg et al. Science 373, 1506 (2021)

[5] L. Delacrétaz et al. SciPost Phys. 3, 025 (2017)

[6] G. Seibold et al. Communications Physics 4, 1 (2021)

[7] S.-D. Chen et al , Science 366, 1099 (2019)

[8] Legros et al. Nat. Phys, 15, 142 (2019)

[9] S. Caprara et al., Communications Physics 5, 10 (2022)