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arXiv · 2409.04371

Topological excitons in moiré MoTe$_2$/WSe$_2$ heterobilayers

Paul Froese·Titus Neupert·Glenn Wagner
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Abstract

Due to the presence of flat Chern bands, moiré transition metal dichalcogenide (TMD) bilayers are a platform to realize strongly correlated topological phases of fermions such as fractional Chern insulators. TMDs are also known to host long-lived excitons, which inherit the topology of the underlying Chern bands. For the particular example of MoTe$_2$/WSe$_2$ heterobilayers we perform a time-dependent Hartree-Fock calculation to identify a regime in the phase diagram where the excitons themselves form a topological flat band. This paves a way towards realizing strongly correlated states of bosons in moiré TMDs.

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Paul Froese, Titus Neupert, Glenn Wagner. 2024-09-27. Topological excitons in moiré MoTe$_2$/WSe$_2$ heterobilayers. https://arxiv.org/abs/2409.04371

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