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Mechanism of pseudogap probed by a local impurity

Qiang-Hua Wang
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Abstract

The response to a local strong non-magnetic impurity in the pseudogap phase is examined in two distinctly different scenarios: phase-fluctuation (PF) of pairing field and d-density-wave (DDW) order. In the PF scenario, the resonance state is generally double-peaked near the Fermi level, and is abruptly broadened by vortex fluctuations slightly above the transition temperature. In the DDW scenario, the resonance is single-peaked and remains sharp up to gradual intrinsic thermal broadening, and the resonance energy is analytically determined to be at minus of the chemical potential.

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Qiang-Hua Wang. 2002-01-18. Mechanism of pseudogap probed by a local impurity. https://doi.org/10.1103/physrevlett.88.057002

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