Abstract
VO and VO are two members of the VO Magnéli series (). At ambient pressure, VO manifests a metal to insulator (MI) transition near K and VO (the exception in the series that does not become insulating at ambient pressure) manifests an antiferromagnetic (AFM) transition with spin density wave character at K. Temperature-dependent resistivity data for VO and VO were measured under pressures up to 7.52 and 6.40 GPa, respectively with critical pressures of GPa for VO and GPa for VO. As the MI transition for VO is suppressed no features associated with an AFM transition in the resistivity are seen. Near the critical pressure for VO where the first-order MI transition disappears, a dependence of the low-temperature resistance can be found. On the other hand, in VO as the second-order, antiferromagnetic transition is brought towards , the resistivity shows a vanishing low-temperature region of Fermi-liquid-like behavior, consistent with proximity to a quantum critical point. Improved hydrostaticity of the pressurized sample space enhances the divergence of the coefficient for VO near the AFM critical pressure, 3.5 GPa.
1 More- Received 17 December 2012
DOI:https://doi.org/10.1103/PhysRevB.87.115140
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