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arXiv · 2305.03265

Breaking electron pairs in the pseudogap regime of SmTiO$_3$/SrTiO$_3$/SmTiO$_3$ quantum wells

Xinyi Wu·Lu Chen·Jianan Li·Megan Briggeman·Patrick B. Marshall·Susanne Stemmer·Patrick Irvin·Jeremy Levy
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Abstract

The strongly correlated two-dimensional electron liquid within SmTiO$_3$/SrTiO$_3$/SmTiO$_3$ quantum well structures exhibits a pseudogap phase when the quantum well width is sufficiently narrow. Using low-temperature transport and optical experiments that drive the quantum-well system out of equilibrium, we find evidence of mobile, long-lived, negatively-charged quasiparticles, consistent with the idea that the pseudogap phase arises from strongly bound electron pairs.

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Xinyi Wu, Lu Chen, Jianan Li, Megan Briggeman, Patrick B. Marshall, Susanne Stemmer, Patrick Irvin, Jeremy Levy. 2023-05-05. Breaking electron pairs in the pseudogap regime of SmTiO$_3$/SrTiO$_3$/SmTiO$_3$ quantum wells. https://arxiv.org/abs/2305.03265

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