Electrical Transport and Quantum Oscillations in the Metallic Spin Supersolid EuCo2Al9

TL;DR

This study investigates the electrical transport properties of EuCo2Al9, revealing anomalies and quantum oscillations that connect electronic behavior with magnetic transitions, thus advancing understanding of metallic spin supersolids.

Contribution

It presents the first systematic analysis of electrical transport in a metallic spin supersolid, demonstrating how electron responses relate to magnetic states and fluctuations.

Findings

Anomalies in resistivity and magnetoresistance linked to Eu2+ spins

Observation of Shubnikov-de Haas oscillations indicating band splitting

Correlation between electrical transport and magnetic transitions

Abstract

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.