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Spin-gapped incoherent metal with preformed pairing in the doped antiferromagnetic Mott insulator

Ki-Seok Kim·Mun Dae Kim
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Abstract

We investigate how the antiferromagnetic Mott insulator evolves into the d-wave BCS superconductor through hole doping. Allowing spin fluctuations in the strong coupling approach, we find a spin-gapped incoherent metal with preformed pairing as an intermediate phase between the antiferromagnetic Mott insulator and d-wave superconductor. This non-Fermi liquid metal is identified with an infrared stable fixed point in the spin-decomposition gauge theory, analogous to the spin liquid insulator in the slave-boson gauge theory. We consider the single particle spectrum and dynamical spin susceptibility in the anomalous metallic phase, and discuss physical implications.

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Ki-Seok Kim, Mun Dae Kim. 2007-08-13. Spin-gapped incoherent metal with preformed pairing in the doped antiferromagnetic Mott insulator. https://doi.org/10.1103/physrevb.77.125103

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