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Competing Orders and Quantum Phase Fluctuations on the Low-Energy Excitations and Pseudogap Phenomena of Cuprate Superconductors

C. -T. Chen·A. D. Beyer·N. -C. Yeh
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Abstract

We investigate the low-energy quasiparticle excitation spectra of cuprate superconductors by incorporating both superconductivity (SC) and competing orders (CO) in the bare Green's function and quantum phase fluctuations in the proper self-energy. Our approach provides consistent explanations for various empirical observations, including the excess subgap quasiparticle density of states, ``dichotomy'' in the momentum-dependent quasiparticle coherence and the temperature-dependent gap evolution, and the presence (absence) of the low-energy pseudogap in hole- (electron-) type cuprates depending on the relative scale of the CO and SC energy gaps.

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C. -T. Chen, A. D. Beyer, N. -C. Yeh. 2007-10-10. Competing Orders and Quantum Phase Fluctuations on the Low-Energy Excitations and Pseudogap Phenomena of Cuprate Superconductors. https://doi.org/10.1016/j.ssc.2007.06.029

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