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arXiv · 2609.20439

VQE Validation on the Mononuclear T1 (Blue-Copper) Site: A Stepping Stone to the Multi-Copper Laccase Cluster

Lucia Malickova
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Abstract

Validating variational quantum eigensolver (VQE) pipelines on realistic chemical systems is a critical stepping stone toward tackling classically intractable molecules. In this work, we report emulator-based validation of the VQE workflow proposed for the copper active site, executed on the LRZ Eviden Qaptiva emulator. A problem-tailored ADAPT-VQE with a full singles-doubles-triples (S+D+T) pool removes over 99% of the correlation error, reaching a stable plateau at 4.03 mEh relative to exact diagonalisation (148 selected operators). This establishes a >40x improvement over the hardware-efficient ansatz (HEA). Finally, we frame these emulator results as a robust baseline for upcoming physical quantum hardware runs on Euro-Q-Exa.

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Lucia Malickova. 2026-09-17. VQE Validation on the Mononuclear T1 (Blue-Copper) Site: A Stepping Stone to the Multi-Copper Laccase Cluster. https://arxiv.org/abs/2609.20439

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