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arXiv · 2203.05136

Influence of the Pd-Si ratio on the valence transition in EuPd$_2$Si$_2$ single crystals

Kristin Kliemt·Marius Peters·Isabel Reiser·Michelle Ocker·Franziska Walther·Doan-My Tran·Eunhyung Cho·Michael Merz·Amir A. Haghighirad·Dominik C. Hezel·Franz Ritter·Cornelius Krellner
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Abstract

Single crystals of intermediate valent EuPd$_2$Si$_2$ were grown from an Eu-rich melt by the Bridgman as well as the Czochralski technique. The chemical and structural characterization of an extracted single crystalline Czochralski-grown specimen yielded a slight variation of the Si-Pd ratio along the growth direction and confirms the existence of a finite Eu(Pd$_{1-m}$Si$_m$)$_2$Si$_2$ homogeneity range. The thorough physical characterization carried out on the same crystal showed that this tiny variation in the composition affects the temperature $T_v$ at which the valence transition occurs. These experiments demonstrate a strong coupling between structural and physical properties in the prototypical valence-fluctuating system EuPd$_2$Si$_2$ and explain the different reported values of $T_v$.

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Kristin Kliemt, Marius Peters, Isabel Reiser, Michelle Ocker, Franziska Walther, Doan-My Tran, Eunhyung Cho, Michael Merz, Amir A. Haghighirad, Dominik C. Hezel, Franz Ritter, Cornelius Krellner. 2022-03-10. Influence of the Pd-Si ratio on the valence transition in EuPd$_2$Si$_2$ single crystals. https://doi.org/10.1021/acs.cgd.2c00475

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