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arXiv · 2606.10548

Interaction-driven dynamics in graphene flakes as a benchmark for quantum simulation

Fabian Eickhoff·Satoshi Ejima·Lukas Windgätter·Florian G. Eich·Hannah Rittich·Sebastian Zanker·Peter Schmitteckert
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Abstract

We study interaction-driven ultrafast dynamics in finite graphene flakes following an optical pump quench in an interacting tight-binding model. By comparing exact real-time evolution with simulations restricted to particle-hole excitation subspaces, we assess when relaxation can be captured by low-order many-body processes and when this is not sufficient. The single-particle orbital entropy provides a compact diagnostic for dynamic correlation growth. For the systems studied here, periodic graphene flakes are well described by low-order excitations, whereas confined geometries require substantial higher-order contributions even for relatively small interaction strengths. The quench protocol combines simple initial-state preparation with strongly correlated dynamics, identifying a promising benchmark problem for future quantum-computing simulations.

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Fabian Eickhoff, Satoshi Ejima, Lukas Windgätter, Florian G. Eich, Hannah Rittich, Sebastian Zanker, Peter Schmitteckert. 2026-06-09. Interaction-driven dynamics in graphene flakes as a benchmark for quantum simulation. https://arxiv.org/abs/2606.10548

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