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arXiv · 2601.07851

LOTUS: Layer-ordered Temporally Unified Schedules For Quantum Approximate Optimization Algorithms

Phuong-Nam Nguyen
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Abstract

In this paper, we introduce LOTUS (Layer-Ordered Temporally-Unified Schedules), which is a framework that restructures QAOA from a high-dimensional, chaotic search into a low-dimensional dynamical system. By replacing independent layer-wise angles with a Hybrid Fourier-Autoregressive (HFA) mapping, LOTUS enforces global temporal coherence while maintaining local flexibility. LOTUS consistently outperforms standard optimizers, achieving up to a $27.2\%$ improvement in expectation values over L-BFGS-B and $20.8\%$ compared with COBYLA. Besides, our proposed method drastically reduces computational costs, requiring over $90\%$ fewer iterations than methods like Powell or SLSQP.

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BibTeXRIS

Phuong-Nam Nguyen. 2026-01-09. LOTUS: Layer-ordered Temporally Unified Schedules For Quantum Approximate Optimization Algorithms. https://arxiv.org/abs/2601.07851

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