Unveiling the 5$f$ electron hybridization process in UPd$_2$Al$_3$ via ARPES and Time-resolved PES

Jiao-Jiao Song; Qi-Yi Wu; Chen Zhang; Steve M. Gilbertson; Peter S. Riseborough; Jan Rusz; John J. Joyce; Kevin S. Graham; Clifford G. Olson; Paul H. Tobash; Eric D. Bauer; Bo Chen; Hao Liu; Yu-Xia Duan; Peter M. Oppeneer; George Rodriguez; Tomasz Durakiewicz; Jian-Qiao Meng

arXiv · 2409.07816

Unveiling the 5$f$ electron hybridization process in UPd$_2$Al$_3$ via ARPES and Time-resolved PES

Jiao-Jiao Song·Qi-Yi Wu·Chen Zhang·Steve M. Gilbertson·Peter S. Riseborough·Jan Rusz·John J. Joyce·Kevin S. Graham·Clifford G. Olson·Paul H. Tobash·Eric D. Bauer·Bo Chen·Hao Liu·Yu-Xia Duan·Peter M. Oppeneer·George Rodriguez·Tomasz Durakiewicz·Jian-Qiao Meng

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Abstract

This study investigates the 5$f$-electron-conduction electron hybridization process in the heavy fermion superconductor UPd$_2$Al$_3$ using a combination of angle-resolved photoemission spectroscopy (ARPES) and time-resolved photoemission spectroscopy (tr-PES). ARPES measurements reveal the formation of a hybridization gap at a temperature of approximately 75 K, which becomes more pronounced as the temperature decreases. Notably, the persistence of a flat U 5$f$ band at temperatures well above the hybridization onset challenges conventional understanding. Our findings demonstrate a non-monotonic temperature dependence of the quasiparticle relaxation time, with an anomalous decrease at 20 K, suggesting complex electronic and magnetic interactions. These findings provide detailed insights into the 5$f$-electron hybridization process in UPd$_2$Al$_3$, with significant implications for the understanding of heavy fermion superconductivity and the role of 5$f$-electron hybridization in uranium-based materials.

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Jiao-Jiao Song, Qi-Yi Wu, Chen Zhang, Steve M. Gilbertson, Peter S. Riseborough, Jan Rusz, John J. Joyce, Kevin S. Graham, Clifford G. Olson, Paul H. Tobash, Eric D. Bauer, Bo Chen, Hao Liu, Yu-Xia Duan, Peter M. Oppeneer, George Rodriguez, Tomasz Durakiewicz, Jian-Qiao Meng. 2024-09-12. Unveiling the 5$f$ electron hybridization process in UPd$_2$Al$_3$ via ARPES and Time-resolved PES. https://arxiv.org/abs/2409.07816

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