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arXiv · 2412.08740

Multiple metamagnetic transitions in helical antiferromagnet CeVGe$_3$

Hanshang Jin·Eun Sang Choi·Hung-Cheng Wu·N. J. Curro·K. Nawa·T. J. Sato·R. Kiyanagi·T. Ohhara·Peter Klavins·Valentin Taufour
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Abstract

We report on neutron diffraction, magnetoresistance, magnetization, and magnetic torque measurements under high magnetic field in the helical antiferromagnet CeVGe$_3$. This compound exhibits Kondo lattice coherence and helical antiferromagnetic (AFM) ordering at ambient pressure, similar to the well-studied CeRhIn$_5$. Our measurements reveal that CeVGe$_3$ undergoes a magnetic transition from an incommensurate (ICM) AFM state to an up-up-down-down commensurate (CM) AFM structure, followed by a transition to a novel phase at higher fields. A quantum phase transition occurs around 21.3 T. This rich magnetic field phase diagram closely resembles that of CeRhIn$_5$. Furthermore, angle-dependent magnetoresistance measurements reveal that all transitions in CeVGe$_3$ occur from the field component along the $ab$ plane. These findings highlight the intricate interplay among exchange interactions, crystal field effects, ground state properties, and crystalline symmetries.

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Hanshang Jin, Eun Sang Choi, Hung-Cheng Wu, N. J. Curro, K. Nawa, T. J. Sato, R. Kiyanagi, T. Ohhara, Peter Klavins, Valentin Taufour. 2024-12-11. Multiple metamagnetic transitions in helical antiferromagnet CeVGe$_3$. https://arxiv.org/abs/2412.08740

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