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arXiv · 1607.01061

Ferromagnetic Quantum Critical Point Avoided by the Appearance of Another Magnetic Phase in LaCrGe$_3$ under Pressure

Valentin Taufour·Udhara S. Kaluarachchi·Rustem Khasanov·Manh Cuong Nguyen·Zurab Guguchia·Pabitra Kumar Biswas·Pietro Bonfá·Roberto De Renzi·Xiao Lin·Stella K. Kim·Eun Deok Mun·Hyunsoo Kim·Yuji Furukawa·Cai-Zhuang Wang·Kai-Ming Ho·Sergey L. Bud'ko·Paul C. Canfield
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Abstract

The temperature-pressure phase diagram of the ferromagnet LaCrGe$_3$ is determined for the first time from a combination of magnetization, muon-spin-rotation and electrical resistivity measurements. The ferromagnetic phase is suppressed near $2.1$~GPa, but quantum criticality is avoided by the appearance of a magnetic phase, likely modulated, AFM$_Q$. Our density functional theory total energy calculations suggest a near degeneracy of antiferromagnetic states with small magnetic wave vectors $Q$ allowing for the potential of an ordering wave vector evolving from $Q=0$ to finite $Q$, as expected from the most recent theories on ferromagnetic quantum criticality. Our findings show that LaCrGe$_3$ is a very simple example to study this scenario of avoided ferromagnetic quantum criticality and will inspire further study on this material and other itinerant ferromagnets.

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Valentin Taufour, Udhara S. Kaluarachchi, Rustem Khasanov, Manh Cuong Nguyen, Zurab Guguchia, Pabitra Kumar Biswas, Pietro Bonfá, Roberto De Renzi, Xiao Lin, Stella K. Kim, Eun Deok Mun, Hyunsoo Kim, Yuji Furukawa, Cai-Zhuang Wang, Kai-Ming Ho, Sergey L. Bud'ko, Paul C. Canfield. 2016-07-04. Ferromagnetic Quantum Critical Point Avoided by the Appearance of Another Magnetic Phase in LaCrGe$_3$ under Pressure. https://doi.org/10.1103/physrevlett.117.037207

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