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arXiv · 1604.01114

Composition induced metal-insulator quantum phase transition in the Heusler type Fe2VAl

Takashi Naka·Artem M. Nikitin·Yu Pan·Anne de Visser·Takayuki Nakane·Fumihiro Ishikawa·Yuh Yamada·Motoharu Imai·Akiyuki Matsushita
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Abstract

We report the magnetism and transport properties of the Heusler compound Fe2+xV1-xAl at -0.10 < x < 0.10 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 around the critical point, which scaled approximately according to the power law. 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.

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Takashi Naka, Artem M. Nikitin, Yu Pan, Anne de Visser, Takayuki Nakane, Fumihiro Ishikawa, Yuh Yamada, Motoharu Imai, Akiyuki Matsushita. 2016-04-05. Composition induced metal-insulator quantum phase transition in the Heusler type Fe2VAl. https://doi.org/10.1088/0953-8984/28/28/285601

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