Charge Order Driven by Fermi-Arc Instability in Bi2201March 7, 2014
The understanding of the origin of superconductivity in cuprates has been hindered by the apparent diversity of intertwining electronic orders in these materials. Physicists from US, Canada, Japan, and Germany, including Prof. Jenny Hoffman, Harvard Physics graduate students Michael Yee and Yang He, and an associate of the Department Anjan Soumyanarayanan, address this problem in their Report in Science (DOI: 10.1126/science.1242996). They describe combining resonant x-ray scattering (REXS), scanning-tunneling microscopy (STM), and angle-resolved photoemission spectroscopy (ARPES) to observe a charge order that appears consistently in surface and bulk, and in momentum and real space within one cuprate family, Bi2Sr2−xLaxCuO6+δ (Bi2201). The observed wave vectors rule out simple antinodal nesting in the single-particle limit but match well with a phenomenological model of a many-body instability of the Fermi arcs. Combined with earlier observations of electronic order in other cuprate families, these findings suggest the existence of a generic charge-ordered state in underdoped cuprates and uncover its intimate connection to the pseudogap regime.
See R. Comin, A. Frano, M. M. Yee, Y. Yoshida, ... et al., "Charge Order Driven by Fermi-Arc Instability in Bi2Sr2−xLaxCuO6+δ," Science 10.1126/science.1242996.DOI: