Quantum critical superconductivity in a dense fermi dilute bose mixture close to mechanical instability

Vibhu Mishra

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arXiv · 2610.03094

Quantum critical superconductivity in a dense fermi dilute bose mixture close to mechanical instability

Vibhu Mishra

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Abstract

We couple a metal to an uncondensed bose gas with repulsive bose-fermi interactions in two dimensions. Within the random phase approximation, we show that the density fluctuations of the bosons, which mediate the effective fermion-fermion attraction, become long ranged on appropriate tuning of interactions. This leads to parametrically enhanced superconducting temperatures $T_c \propto g$ as opposed to $T_c \propto \exp(-1/g)$ for the BCS case. The dilute bose gas density acts as the primary bottleneck to the enhancement. We discuss the conceptual difficulties of implementing this idea in electron-exciton mixtures.

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Vibhu Mishra. 2026-10-02. Quantum critical superconductivity in a dense fermi dilute bose mixture close to mechanical instability. https://arxiv.org/abs/2610.03094

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