Hamidian, M. H.Edkins, S. D.Kim, Chung KooDavis, J. C.Mackenzie, A. P.Eisaki, H.Uchida, S.Lawler, M. J.Kim, E.-A.Sachdev, SubirFujita, K.2016-06-102015Hamidian, M. H., S. D. Edkins, Chung Koo Kim, J. C. Davis, A. P. Mackenzie, H. Eisaki, S. Uchida, et al. 2015. “Atomic-Scale Electronic Structure of the Cuprate d-Symmetry Form Factor Density Wave State.” Nature Physics 12 (2) (October 26): 150–156. doi:10.1038/nphys3519.1745-2473http://nrs.harvard.edu/urn-3:HUL.InstRepos:27303653Research on high-temperature superconducting cuprates is at present focused on identifying the relationship between the classic ‘pseudogap’ phenomenon and the more recently investigated density wave state. This state is generally characterized by a wavevector Q parallel to the planar Cu–O–Cu bonds along with a predominantly d-symmetry form facto (dFF-DW). To identify the microscopic mechanism giving rise to this state one must identify the momentum-space states contributing to the dFF-DW spectral weight, determine their particle–hole phase relationship about the Fermi energy, establish whether they exhibit a characteristic energy gap, and understand the evolution of all these phenomena throughout the phase diagram. Here we use energy-resolved sublattice visualization14 of electronic structure and reveal that the characteristic energy of the dFF-DW modulations is actually the ‘pseudogap’ energy Δ1. Moreover, we demonstrate that the dFF-DW modulations at E  =   −Δ1 (filled states) occur with relative phase π compared to those at E  =  Δ1 (empty states). Finally, we show that the conventionally defined dFF-DW Q corresponds to scattering between the ‘hot frontier’ regions of momentum-space beyond which Bogoliubov quasiparticles cease to exist. These data indicate that the cuprate dFF-DW state involves particle–hole interactions focused at the pseudogap energy scale and between the four pairs of ‘hot frontier’ regions in momentum space where the pseudogap opens.en-USElectronic properties and materialsSuperconducting properties and materialsJournal Article2016-06-1010.1038/nphys3519