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Bound states in d-density-wave phases

Carsten Honerkamp·Manfred Sigrist
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Abstract

We investigate the quasiparticle spectrum near surfaces in a two-dimensional system with d-density-wave order within a mean-field theory. For Fermi surfaces with perfect nesting for the ordering wave vector of the d-density-wave, a zero energy bound state occurs at [110] surfaces, in close analogy with the known effect in d-wave superconducting states or graphite. When the shape of the Fermi surface is changed by doping, the bound state energy moves away from the Fermi level. Furthermore, away from half-filling we find inhomogeneous phases with domain walls of the d-density-wave order parameter. The domain walls also support low energy bound states. These phenomena might provide an experimental test for hidden d-density-wave order in the high-Tc cuprates.

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Carsten Honerkamp, Manfred Sigrist. 2001-07-26. Bound states in d-density-wave phases. https://doi.org/10.1088/0953-8984%2F13%2F50%2F326

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