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arXiv · 2204.05342

Phonon-induced modification of quantum criticality

Abhisek Samanta·Efrat Shimshoni·Daniel Podolsky
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Abstract

We study the effect of acoustic phonons on the quantum phase transition in the O($N$) model. We develop a renormalization group analysis near (3+1) space-time dimensions and derive the RG equations using an $\epsilon$-expansion. Our results indicate that when the number of flavors of the underlying O($N$) model exceeds a critical number $N_c=4$, the quantum transition remains second-order of the Wilson-Fisher type while, for $N\le 4$, it is a weakly first-order transition. We characterize this weakly first-order transition by a length-scale $\xi^*$, below which the behavior appears to be critical. At finite temperatures for $N\le 4$, a tricritical point separates the weakly first-order and second-order transitions.

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Abhisek Samanta, Efrat Shimshoni, Daniel Podolsky. 2022-04-11. Phonon-induced modification of quantum criticality. https://doi.org/10.1103/physrevb.106.035154

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