Cheng, Hsu-KaiHsu-KaiChengYang, Po-YuPo-YuYangJYH PIN CHOUPao, Chun-WeiChun-WeiPao2026-04-132026-04-132026-01-22https://www.scopus.com/record/display.uri?eid=2-s2.0-105033736322&origin=resultslisthttps://scholars.lib.ntu.edu.tw/handle/123456789/737095Accurate machine-learning (ML) prediction of material energies typically relies on large models with thousands to hundreds of thousands of parameters and scales poorly with the system size. Here, we present a compact hybrid classical-quantum ML framework that predicts the energies of complex materials using fewer than ten qubits, regardless of system size. By compressing local atomic descriptors into a fixed-size feature spectrum, we enable amplitude encoding of chemically diverse systems into shallow quantum circuits. We implement quantum convolutional neural networks (QCNNs) and quantum deep neural networks (QDNNs) with fewer than 100 trainable parameters and achieve prediction errors below 0.05 eV/atom on chemically complex alloys (Co25 Ni25(Hf Ti Zr)50) and lithium-intercalated metal-organic frameworks. Our results demonstrate the feasibility of scalable quantum assisted materials modeling and introduce a resource-efficient route toward quantum machine learning for atomistic simulations.truePredicting Complex Materials Energetics with a Scalable Compact Nine-Qubit Quantum Machine-Learning Modeljournal article10.1103/j1lk-1cvs2-s2.0-105033736322