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arXiv · 2607.22283

When Can a Cavity Move a Mott Transition? A Spectral-Density Criterion within Gutzwiller Theory

Nikhil Vamsodharakan Seshadri·Yu Zhang
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Abstract

Can vacuum electromagnetic fluctuations shift a bulk Mott transition? Within the Gutzwiller variational method, we derive a criterion that separates collective spectroscopic hybridization from thermodynamic phase control. We show that a Mott transition shifts only when the electromagnetic environment supplies finite thermodynamic spectral weight with bond-scale variation. A joint frequency--spatial Pauli--Fierz density gives the leading shift. Surface phonon polaritons yield a $d^{-3}$-to-$d^{-5}$ crossover, while finite-coordination variational Monte Carlo supports the predicted critical coefficient and $M/N$ scaling.

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Nikhil Vamsodharakan Seshadri, Yu Zhang. 2026-07-24. When Can a Cavity Move a Mott Transition? A Spectral-Density Criterion within Gutzwiller Theory. https://arxiv.org/abs/2607.22283

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