TY - GEN A1 - Miao, Hu A1 - Fumagalli, Roberto A1 - Rossi, M. A1 - Lorenzana, José A1 - Seibold, Götz A1 - Yakhou-Harris, Flora A1 - Kummer, K. A1 - Brookes, Nicholas B. A1 - Gu, G. D. A1 - Braicovich, Lucio A1 - Ghiringhelli, Giacomo Claudio A1 - Dean, M. P. M. T1 - Formation of Incommensurate Charge Density Waves in Cuprates T2 - Physical Review X N2 - Although charge density waves (CDWs) are omnipresent in cuprate high-temperature superconductors, they occur at significantly different wave vectors, confounding efforts to understand their formation mechanism. Here, we use resonant inelastic x-ray scattering to investigate the doping- and temperature-dependent CDW evolution in La₂₋ₓBaₓCuO₄ (x=0.115–0.155). We discover that the CDW develops in two stages with decreasing temperature. A precursor CDW with a quasicommensurate wave vector emerges first at high temperature. This doping-independent precursor CDW correlation originates from the CDW phase mode coupled with a phonon and “seeds” the low-temperature CDW with a strongly doping-dependent wave vector. Our observation reveals the precursor CDW and its phase mode as the building blocks of the highly intertwined electronic ground state in the cuprates. KW - Research Areas Charge density waves KW - Electrical Properties KW - Cuprates KW - Strongly correlated systems KW - Resonant inelastic x-ray scattering KW - Superconductivity Y1 - 2019 UR - https://journals.aps.org/prx/abstract/10.1103/PhysRevX.9.031042 U6 - https://doi.org/10.1103/PhysRevX.9.031042 SN - 2160-3308 VL - 9 IS - 3 SP - 031042-1 EP - 031042-11 ER - TY - GEN A1 - Seibold, Götz A1 - Arpaia, Riccardo A1 - Ying Ying, Peng A1 - Fumagalli, Roberto A1 - Braicovich, Lucio A1 - Di Castro, Carlo A1 - Grilli, Marco A1 - Ghiringhelli, Giacomo Claudio A1 - Caprara, Sergio T1 - Strange metal behaviour from charge density fluctuations in cuprates T2 - Communications Physics N2 - Besides the mechanism responsible for high critical temperature superconductivity, the grand unresolved issue of the cuprates is the occurrence of a strange metallic state above the so-called pseudogap temperature T*. Even though such state has been successfully described within a phenomenological scheme, the so-called Marginal Fermi-Liquid theory, a microscopic explanation is still missing. However, recent resonant X-ray scattering experiments identified a new class of charge density fluctuations characterized by low characteristic energies and short correlation lengths, which are related to the well-known charge density waves. These fluctuations are present over a wide region of the temperature-vs-doping phase diagram and extend well above T*. Here we investigate the consequences of charge density fluctuations on the electron and transport properties and find that they can explain the strange metal phenomenology. Therefore, charge density fluctuations are likely the long-sought microscopic mechanism underlying the peculiarities of the metallic state of cuprates. KW - Electronic properties and materials KW - Superconducting properties and materials Y1 - 2021 UR - https://www.nature.com/articles/s42005-020-00505-z U6 - https://doi.org/10.1038/s42005-020-00505-z SN - 2399-3650 VL - 4 SP - 1 EP - 6 ER - TY - GEN A1 - Miao, Hu A1 - Lorenzana, José A1 - Seibold, Götz A1 - Peng, Yingying A1 - Amorese, Andrea A1 - Yakhou-Harris, Flora A1 - Kummer, Kurt A1 - Brookes, Nicholas B. A1 - Konik, R. M. A1 - Thampy, Vivek A1 - Gu, G. D. A1 - Ghiringhelli, Giacomo Claudio A1 - Braicovich, Lucio A1 - Dean, M. P. M. T1 - High-temperature charge density wave correlations in La1.875Ba0.125CuO4 without spin–charge locking T2 - Proceedings of the National Academy of Sciences of the United States of America PNAS N2 - Although all superconducting cuprates display charge-ordering tendencies, their low-temperature properties are distinct, impeding efforts to understand the phenomena within a single conceptual framework. While some systems exhibit stripes of charge and spin, with a locked periodicity, others host charge density waves (CDWs) without any obviously related spin order. Here we use resonant inelastic X-ray scattering to follow the evolution of charge correlations in the canonical stripe-ordered cuprate La1.875Ba0.125CuO4 across its ordering transition. We find that high-temperature charge correlations are unlocked from the wavevector of the spin correlations, signaling analogies to CDW phases in various other cuprates. This indicates that stripe order at low temperatures is stabilized by the coupling of otherwise independent charge and spin density waves, with important implications for the relation between charge and spin correlations in the cuprates. KW - charge density waves KW - stripes KW - high-temperature superconductivity KW - cuprates KW - X-rays Y1 - 2017 UR - http://www.pnas.org/content/early/2017/10/31/1708549114.abstract U6 - https://doi.org/10.1073/pnas.1708549114 SN - 1091-6490 SN - 0027-8424 VL - 114 IS - 47 SP - 12430 EP - 12435 ER - TY - GEN A1 - Wahlberg, Eric A1 - Arpaia, Riccardo A1 - Seibold, Götz A1 - Rossi, Matteo A1 - Fumagalli, Roberto A1 - Trabaldo, Edoardo A1 - Brookes, Nicholas B. A1 - Braicovich, Lucio A1 - Caprara, Sergio A1 - Lombardi, Floriana A1 - Gran, Ulf A1 - Ghiringhelli, Giacomo Claudio A1 - Bauch, Thilo T1 - Restored strange metal phase through suppression of charge density waves in underdoped YBa2Cu3O7–δ T2 - Science N2 - The normal state of optimally doped cuprates is dominated by the “strange metal” phase that shows a linear temperature (T) dependence of the resistivity persisting down to the lowest T. For underdoped cuprates, this behavior is lost below the pseudogap temperature T*, where charge density waves (CDWs), together with other intertwined local orders, characterize the ground state. We found that the T-linear resistivity of highly strained, ultrathin, underdoped YBa2Cu3O7–δ films is restored when the CDW amplitude, detected by resonant inelastic x-ray scattering, is suppressed. This observation suggests an intimate connection between the onset of CDWs and the departure from T-linear resistivity in underdoped cuprates. Our results illustrate the potential of using strain control to manipulate the ground state of quantum materials. KW - Cuprate superconductors KW - Charge-Density Wave Y1 - 2021 UR - https://www.science.org/doi/10.1126/science.abc8372 U6 - https://doi.org/10.1126/science.abc8372 VL - 373 IS - 6562 SP - 1506 EP - 1510 ER -