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Quantum critical phase in BaVS$_3$

N. Barišić·I. Kézsmárki·P. Fazekas·G. Mihály·H. Berger·L. Demkó·L. Forró
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Abstract

We study the high-pressure metallic phase of high-purity single crystals of BaVS$_3$ by measuring the temperature, pressure, and magnetic field dependence of the resistivity. Above the critical pressure of $p_{\rm cr}=1.97$GPa an extended non-Fermi liquid $p-T$ regime emerges with resistivity exponent $1.5 \le n<2$, crossing over to a FL only around $p=2.7$GPa. A hysteretic feature indicates that close to the insulator--metal boundary, the system is magnetically ordered. Our findings reveal a close analogy between the extended partially ordered NFL state of non-conventional itinerant magnets and the corresponding state of BaVS$_3

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N. Barišić, I. Kézsmárki, P. Fazekas, G. Mihály, H. Berger, L. Demkó, L. Forró. 2006-02-10. Quantum critical phase in BaVS$_3$. https://arxiv.org/abs/cond-mat/0602262

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