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Microscopic phase separation in the overdoped region of high-Tc cuprate superconductors

Y. J. Uemura
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Abstract

We propose a phenomenological model for high-$T_{c}$ superconductors (HTSC) assuming: (1) a microscopic phase separation between superconducting and normal-metal areas in the overdoped region; and (2) existence of a homogeneous superconducting phase only below the pseudo-gap $T^{*}$ line, which shows a sharp reduction towards $T^{*}\sim 0$ at a mildly overdoped critical concentration $x_{c}$. This model explains anomalous doping and temperature dependences of $n_{s}/m^{*}$ (superconducting carrier density / effective mass) observed in several overdoped HTSC systems. We point out an analogy to superfluid $^{4}$He/$^{3}$He films, and discuss an energetic origin of microscopic phase separation.

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Y. J. Uemura. 2001-10-31. Microscopic phase separation in the overdoped region of high-Tc cuprate superconductors. https://doi.org/10.1016/s0038-1098(01)00410-0

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