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arXiv · 1910.10349

Quantum Valence Criticality in Heavy Fermions on Periodic and Aperiodic Crystals

Shinji Watanabe·Kazumasa Miyake
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Abstract

Progress of theories and experiments of the quantum valence criticality is overviewed focusing on recent discoveries of direct evidence of quantum critical point of valence transitions in periodic crystal $\alpha$-YbAl$_{1-x}$Fe$_x$B$_4$ at $x=0.014$ and quasicrystal Yb$_{15}$(Al$_{1-x} $Ga$_{x}$)$_{34}$(Au$_{1-y}$Cu$_{y}$)$_{51}$ at $x=y=0$. The common quantum criticality as well as $T/B$ scaling behavior in the magnetization observed in the periodic crystal $\beta$-YbAlB$_4$ and quasicrystal Yb$_{15}$Al$_{34}$Au$_{51}$ is shown to be explained from the theory of critical Yb-valence fluctuations starting from the Hamiltonians for describing the low-energy electronic states in both systems.

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Shinji Watanabe, Kazumasa Miyake. 2019-10-23. Quantum Valence Criticality in Heavy Fermions on Periodic and Aperiodic Crystals. https://doi.org/10.7566/jpscp.30.011023

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