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Non-magnetic impurities as probes of insulating and doped Mott insulators in two dimensions

Subir Sachdev·Matthias Vojta
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Abstract

We characterize paramagnetic Mott insulators by their response to static, non-magnetic impurities. States with spinon deconfinement (or spin-charge separation) are distinguished from those with spinon confinement by distinct impurity susceptibilities and finite-size spectra. We discuss the evolution of physical properties upon doping to a d-wave superconductor, and argue that a number of recent experiments favor spinon confinement in the reference Mott insulating state.

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Subir Sachdev, Matthias Vojta. 2000-11-02. Non-magnetic impurities as probes of insulating and doped Mott insulators in two dimensions. https://arxiv.org/abs/cond-mat/0009202

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