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arXiv · 1501.03852

High Pressure Measurements of the Resistivity of $β$-YbAlB$_4$

Takahiro Tomita·Kentaro Kuga·Yoshiya Uwatoko·Satoru Nakatsuji
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Abstract

The electric resistivity $ρ(T)$ under hydrostatic pressure up to 8 GPa was measured above 2 K using a high-quality single crystal of the Yb-based heavy fermion system $β$-YbAlB$_4$. We found pressure-induced magnetic ordering above the critical pressure $P_{\rm c} \approx $ 2.4 GPa. This phase transition temperature $T_M$ is enhanced with pressure and reaches 30 K at a pressure of 8 GPa, which is the highest transition temperature for the Yb-based heavy fermion compounds. In contrast, the resistivity is insensitive to pressure below $P_c$ and exhibits the $T$-linear behavior in the temperature range between 2 and 20 K. Our results indicate that quantum criticality for $β$-YbAlB$_4$ is also located near $P_{\rm c}$ in addition to the ambient pressure.

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Takahiro Tomita, Kentaro Kuga, Yoshiya Uwatoko, Satoru Nakatsuji. 2015-01-15. High Pressure Measurements of the Resistivity of $β$-YbAlB$_4$. https://doi.org/10.1088/1742-6596%2F592%2F1%2F012019

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