RESUMO
We report the magnetism and transport properties of the Heusler compound Fe2+x V1-x Al at -0.10 ⩽ x ⩽ 0.20 under pressure and a magnetic field. A metal-insulator quantum phase transition occurred at x ≈ -0.05. Application of pressure or a magnetic field facilitated the emergence of finite zero-temperature conductivity σ 0 around the critical point, which scaled approximately according to the power law (P - P c ) (γ) . At x ⩽ -0.05, a localized paramagnetic spin appeared, whereas above the ferromagnetic quantum critical point at x ≈ 0.05, itinerant ferromagnetism was established. At the quantum critical points at x = -0.05 and 0.05, the resistivity and specific heat exhibited singularities characteristic of a Griffiths phase appearing as an inhomogeneous electronic state.