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arXiv · 2610.29366

Hybridization-Induced Enhancement of the Thermoelectric Response in the Kagome Material CsCr$_6$Sb$_6$

Hongye Zhang·Boqin Song·Aifeng Wang·Yisheng Chai·Xiaoyuan Zhou·Ying Zhu·Tianping Ying·Mingquan He
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Abstract

Flat bands in kagome lattices provide a prominent route to strongly correlated electronic states. Here we report charge and thermal transport measurements on single crystals of CsCr$_6$Sb$_6$, a kagome Kondo system arising from the hybridization between flat and dispersive bands. The Seebeck coefficient and Nernst signal increase rapidly below $T_\mathrm{F}\sim70$ K, concomitant with the emergence of short-range antiferromagnetic correlations and flat-band resonance. The Nernst coefficient in the intermediate-temperature range of $\sim30-80$ K further follows the universal scaling reported for prototypical heavy-fermion compounds, consistent with the development of strongly renormalized quasiparticles associated with hybridization. Both the Seebeck and Nernst responses reach extrema at a lower temperature $T_\mathrm{p}\sim20-25$ K, where phonon drag and correlated quasiparticles may both contribute. These results reveal a hybridization-induced enhancement of the thermoelectric response and establish CsCr$_6$Sb$_6$ as a kagome platform for probing flat-band-derived Kondo physics through thermoelectric transport.

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Hongye Zhang, Boqin Song, Aifeng Wang, Yisheng Chai, Xiaoyuan Zhou, Ying Zhu, Tianping Ying, Mingquan He. 2026-10-21. Hybridization-Induced Enhancement of the Thermoelectric Response in the Kagome Material CsCr$_6$Sb$_6$. https://arxiv.org/abs/2610.29366

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