V3O5 at high pressure: a possible heavy fermion 3d-metal oxide

The electrical resistivity ρ of V3O5 was measured at pressures to 10 GPa in the temperature range 4.2–500 K. The semiconductor–metal transition (Tc=428 K at normal pressure) shifts to lower temperatures at high pressure, and for ∼4≤P≤9 GPa, there are two successive resistive transitions. The stability range of an intermediate phase at 6 GPa, 300 K extends over few Kelvin and systematically expands on further pressure increase. Both transitions are completely suppressed at pressures of 8–9 GPa and the ground state is metallic. The electrical resistivity of the pressure-induced metallic state of V3O5 shows features typical of heavy fermion compounds: a pronounced maximum in ρ(T) below 100 K and a large T2 coefficient of the low temperature resistivity.