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arXiv · 0804.4734

Magnetic-Field Control of Quantum Critical Points of Valence Transition

Shinji Watanabe·Atsushi Tsuruta·Kazumasa Miyake·Jacques Flouquet
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Abstract

We study the mechanism how critical end points of first-order valence transitions are controlled by a magnetic field. We show that the critical temperature is suppressed to be a quantum critical point (QCP) by a magnetic field and unexpectedly the QCP exhibits nonmonotonic field dependence in the ground-state phase diagram, giving rise to emergence of metamagnetism even in the intermediate valence-crossover regime. The driving force of the field-induced QCP is clarified to be cooperative phenomena of Zeeman effect and Kondo effect, which create a distinct energy scale from the Kondo temperature. This mechanism explains peculiar magnetic response in CeIrIn5 and metamagnetic transition in YbXCu4 for X=In as well as sharp contrast between X=Ag and Cd.

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Shinji Watanabe, Atsushi Tsuruta, Kazumasa Miyake, Jacques Flouquet. 2008-06-11. Magnetic-Field Control of Quantum Critical Points of Valence Transition. https://doi.org/10.1103/physrevlett.100.236401

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