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arXiv · 0909.0322

Unconventional Low-Energy Excitations of Cuprate Superconductors

N. -C. Yeh·A. D. Beyer
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Abstract

Recent development in the physics of high-temperature cuprate superconductivity is reviewed, with special emphasis on the phenomena of unconventional and non-universal low-energy excitations of hole- and electron-type cuprate superconductors and the possible physical origin. A phenomenology based on coexisting competing orders with cuprate superconductivity in the ground state appears to provide consistent account for a wide range of experimental findings, including the presence (absence) of pseudogaps and Fermi arcs above the superconducting transition $T_c$ in hole-type (electron-type) cuprate superconductors and the novel conductance modulations below $T_c$, particularly in the vortex state. Moreover, the competing order scenario is compatible with the possibility of pre-formed Cooper pairs and significant phase fluctuations in cuprate superconductors. The physical implications of the unified phenomenology and remaining open issues for the microscopic mechanism of cuprate superconductivity are discussed.

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N. -C. Yeh, A. D. Beyer. 2009-09-02. Unconventional Low-Energy Excitations of Cuprate Superconductors. https://doi.org/10.1142/s021797920905403x

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