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Quantum Critical Point in Electron-Doped Cuprates

C. Kusko·R. S. Markiewicz·M. Lindroos·A. Bansil
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Abstract

We analyze doping dependent spectral intensities and Fermi surface maps obtained recently in Nd$_{2-x}$Ce$_x$CuO$_{4\pmδ}$ (NCCO) via high resolution ARPES measurements, and show that the behavior of this electron-doped compound can be understood as the closing of a Mott (pseudo) gap, leading to a quantum critical point just above optimal doping. The doping dependence of the effective Hubbard $U$ adduced by comparing theoretical and experimental spectra is in resonable accord with various estimates and a simple screening calculation.

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C. Kusko, R. S. Markiewicz, M. Lindroos, A. Bansil. 2002-01-08. Quantum Critical Point in Electron-Doped Cuprates. https://arxiv.org/abs/cond-mat/0201117

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