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arXiv · 2412.12748

Revealing spinons by proximity effect

Antonio Maria Tagliente·Carlos Mejuto-Zaera·Michele Fabrizio
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Abstract

The ghost-Gutzwiller variational wavefunction within the Gutzwiller approximation is shown to stabilize a genuine paramagnetic Mott insulator in the half-filled single-band Hubbard model. This phase hosts quasiparticles that are crucial to the paramagnetic response without showing up in the single-particle spectrum, and, as such, they can be legitimately regarded as an example of Anderson's spinons. We demonstrate that these spinons at the interface with a metal reacquire charge by proximity effect and thus reemerge in the spectrum as a heavy-fermion band.

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Antonio Maria Tagliente, Carlos Mejuto-Zaera, Michele Fabrizio. 2024-12-17. Revealing spinons by proximity effect. https://doi.org/10.1103/physrevb.111.125110

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