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arXiv · 2106.08354

Superconducting-like response in driven systems near the Mott transition

Zhehao Dai·Patrick A. Lee
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Abstract

We point out that fractionalized bosonic charge excitations can explain the recently discovered photo-induced superconducting-like response in $\kappa\text{-(ET})_2\text{Cu}[\text{N(CN)}_2]\text{Br}$, an organic metal close to the Mott transition. The pump laser exerts a periodic drive on the fractionalized field, creating a non-equilibrium condensate, which gives a Drude peak much narrower than the equilibrium scattering rate, hence superconducting-like response. Our proposal illuminates new possibilities of detecting fractionalization and can be readily tested in spin liquid candidates and in cold atom systems.

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Zhehao Dai, Patrick A. Lee. 2021-06-15. Superconducting-like response in driven systems near the Mott transition. https://doi.org/10.1103/physrevb.104.l241112

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