B. Loret, et al., “Intimate link between charge density wave, pseudogap and superconducting energy scales in cuprates”, Nature Physics, vol. 15, p. 771-775, 2019. WebsiteAbstract
The cuprate high-temperature superconductors develop spontaneous charge density wave (CDW) order below a temperature TCDW and over a wide range of hole doping (p). An outstanding challenge in the field is to understand whether this modulated phase is related to the more exhaustively studied pseudogap and superconducting phases1,2. To address this issue, it is important to extract the energy scale DCDW associated with the CDW order, and to compare it with the pseudogap DPG and with the superconducting gap DSC. However, while TCDW is well characterized from earlier work3, little is currently known about DCDW. Here, we report the extraction of DCDW for several cuprates using electronic Raman spectroscopy. We find that on approaching the parent Mott state by lowering p, DCDW increases in a manner similar to the doping dependence of DPG and DSC. This reveals that these three phases have a common microscopic origin. In addition, we find that DCDW [?] DSC over a substantial doping range, which suggests that CDW and superconducting phases are intimately related; for example, they may be intertwined or connected by an emergent symmetry1,4-9.