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arXiv · 2111.12250

Analysis of Fr\"ohlich bipolarons

L. Lin·P. B. Littlewood·A. Edelman
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Abstract

Following a resurgence of interest in dilute superconductivity in polar semiconductors, we perform a variational calculation to probe the existence of Fr{\"o}hlich bipolarons in these materials. Our solution is capable of interpolating between the weak- and strong-coupling limits of the electron-phonon interaction. We predict bipolaron formation in solely the strong-coupling regime, and we are not aware of any existing materials at these parameter values. However, imposing an extrinsic electron size constraint to mimic confinement on the sub-micron scale produces binding in new parts of the phase diagram, including at weak coupling, within reach of the near-ferroelectric perovskites.

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L. Lin, P. B. Littlewood, A. Edelman. 2021-11-24. Analysis of Fr\"ohlich bipolarons. https://arxiv.org/abs/2111.12250

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