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arXiv · 2509.09817

Pressure tuning of putative quantum criticality on YbV6Sn6

P. C. Sabino·L. Mendonça-Ferreira·J. G. Dias·G. G. Vasques·M. Dutra·H. Pizzi·P. G. Pagliuso·M. A. Avila
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Abstract

YbV$_6$Sn$_6$ is a recently discovered heavy-fermion compound that orders at T$_N\approx 0.4$ K and exhibits a magnetic field-tuned quantum critical point at $H \approx 10$ kOe. In this work, we have grown YbV$_6$Sn$_6$ single crystals by the self-flux method, to investigate their physical properties at ambient pressure and their electrical transport properties under hydrostatic pressure. At higher temperatures, we observed a decrease in the Kondo temperature, accompanied by the appearance of a local minimum followed by a local maximum, associated with the onset of the coherent Kondo regime. Power law fitting at low temperatures indicated a recovery of the Fermi-liquid regime for pressures below 1 GPa. Above 1 GPa, a reentrance of non-Fermi-liquid behavior is suggested by a decrease in the exponent $n$, accompanied by a substantial increase in the parameter $A$, indicating the approach of a new quantum criticality tuned by hydrostatic pressure. The broad range of interactions present in YbV$_6$Sn$_6$, including RKKY, crystalline electric field (CEF), and Kondo lattice effects, appears to lead to a complex phase diagram. We present a putative phase diagram featuring double quantum criticality tuned by both magnetic field and hydrostatic pressure.

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P. C. Sabino, L. Mendonça-Ferreira, J. G. Dias, G. G. Vasques, M. Dutra, H. Pizzi, P. G. Pagliuso, M. A. Avila. 2025-09-11. Pressure tuning of putative quantum criticality on YbV6Sn6. https://arxiv.org/abs/2509.09817

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