Correlated magnetism of moir\'e exciton-polaritons on a triangular electron-spin lattice

Johannes Scherzer; Lukas Lackner; Bo Han; Borislav Polovnikov; Lukas Husel; Jonas Göser; Zhijie Li; Jens-Christian Drawer; Martin Esmann; Christoph Bennenhei; Falk Eilenberger; Kenji Watanabe; Takashi Taniguchi; Anvar S. Baimuratov; Christian Schneider; Alexander Högele

arXiv · 2405.12698

Correlated magnetism of moir\'e exciton-polaritons on a triangular electron-spin lattice

Johannes Scherzer·Lukas Lackner·Bo Han·Borislav Polovnikov·Lukas Husel·Jonas Göser·Zhijie Li·Jens-Christian Drawer·Martin Esmann·Christoph Bennenhei·Falk Eilenberger·Kenji Watanabe·Takashi Taniguchi·Anvar S. Baimuratov·Christian Schneider·Alexander Högele

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Abstract

We demonstrate evidence of correlated magnetism for exciton-polaritons in a MoSe$_{2}$/WS$_{2}$ moir\'e heterostructure with near-parallel alignment subject to electron doping. In our experiments, interactions between electrons and moir\'e excitons are controlled electrostatically by field-effect doping, and the polaritonic regime of strong light-matter coupling is established in an open cryogenic microcavity. Remarkably, at filling fractions around one electron per moir\'e cell, we observe drastic and nonlinear enhancement of the effective polariton Land\'e factor as a hallmark of correlated magnetism, which is cavity-controlled via resonance tuning of light and matter polariton constituents. Our work establishes moir\'e van der Waals heterostructures as an outstanding platform for studies of correlated phenomena in the presence of strong light-matter coupling and many-body phases of lattice-ordered excitons, charges and spins.

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Johannes Scherzer, Lukas Lackner, Bo Han, Borislav Polovnikov, Lukas Husel, Jonas Göser, Zhijie Li, Jens-Christian Drawer, Martin Esmann, Christoph Bennenhei, Falk Eilenberger, Kenji Watanabe, Takashi Taniguchi, Anvar S. Baimuratov, Christian Schneider, Alexander Högele. 2024-05-21. Correlated magnetism of moir\'e exciton-polaritons on a triangular electron-spin lattice. https://arxiv.org/abs/2405.12698

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