Resistivity modulation of perovskite samarium nickelate with high-valence cations and the underlying mechanism

Perovskite rare earth nickelates possess the electronic phase transition property that can be harnessed for a multitude of exciting applications. Herein, we report the use of high-valence cations (Zn 2+ and Al 3+ ) to reconstruct the electronic band structure of samarium nickelate (SmNiO 3 ) and realize reversible resistivity modulation. Under positive gate voltage, the resistivity of SmNiO 3 exhibits a colossal increase upon the Zn 2+ intercalation and the concurrent electron doping. Under negative gate voltage, the Zn 2+ ions are extracted and the resistivity decreases significantly. The resistivity modulation using Zn 2+ is non-volatile. Electrochromic behavior is also observed during the Zn 2+ insertion and extraction. The electronic phase transition is characterized using various techniques. Moreover, the trivalent Al 3+ ions are also investigated as charge carriers to modulate the resistivity of SmNiO 3 in a volatile manner. First-principles density functional theory calculations reveal the effect of electron doping on the electronic band structure. The resistivity change of SmNiO 3 is mainly attributed to the structural distortion induced by electron doping, rather than the Mott-like insulation. This work demonstrates the feasibility of reversible resistivity modulation of SmNiO 3 with the use of high-valence cations under applied voltage, underscoring the potential for applications in novel emerging electronic devices.