We report the crystal growth of a new compound, Yb3Os4Ge13, by using a Bi-flux method. X-ray diffraction measurement shows that it crystallizes in the quasi-skutterudite-type caged structure with a cubic space group of Pm-3n (No. 223). Magnetic measurements reveal almost fully localized Yb f-moments above 120 K. The resistivity exhibits a crossover from metallic to insulating behavior with a logarithmic increase below ~ 40 K. The specific heat coefficient shows a rapid upturn below ~5 K and exceeds 2 J mol-1 K-2 at 2 K. Our experimental analysis and electronic band structure calculations demonstrate that Yb3Os4Ge13 exhibits the Kondo effect due to strong hybridization of the localized Yb f-moments with the p-electrons of the surrounding Ge-cages.
@article{arxiv.1411.1616,
title = {Kondo effect in a novel 5d quasi-skutterudite Yb3Os4Ge13},
author = {C. L. Yang and X. Wang and X. Zhang and D. S. Wu and M. Liu and P. Zheng and J. Y. Yao and Z. Z. Li and Y. F. Yang and Y. G. Shi and J. L. Luo and N. L. Wang},
journal= {arXiv preprint arXiv:1411.1616},
year = {2016}
}