The discovery of spin supersolid and its giant magnetocaloric effect has opened a new arena in frustrated quantum magnets and cutting-edge cryogenics. The intermetallic EuCo2Al9 (ECA), for the first time, extends this intriguing phase from Mott insulators to a highly conductive metal [1]. In this work, we systematically study the electrical transport properties of ECA, where itinerant electrons serve as a sensitive probe for the spin supersolid states. We observe anomalies both in the temperature-dependent resistivity and field-dependent magnetoresistance and Hall signals, which are attributed to response of electrons to the Eu2+ spins and their fluctuations. Moreover, Shubnikov-de Haas quantum oscillations at high magnetic field reveal pronounced band splitting in the spin polarized state. Our results reveal an intimate correspondence between electrical transport and magnetic transitions in ECA, deepening the understanding of this metallic spin supersolid.
@article{arxiv.2603.24445,
title = {Electrical Transport and Quantum Oscillations in the Metallic Spin Supersolid EuCo2Al9},
author = {Xitong Xu and Yonglai Liu and Ning Xi and Mingfang Shu and Haitian Zhao and Jiajun Xie and Guoliang Wu and Hao Chen and Miao He and Pengzhi Chen and Ze Wang and Zhentao Wang and Chuanying Xi and Mingliang Tian and Haifeng Du and Jie Ma and Xi Chen and Wei Li and Zhe Qu},
journal= {arXiv preprint arXiv:2603.24445},
year = {2026}
}