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 (Zn2+ and Al3+) to reconstruct the electronic band structure of samarium nickelate (SmNiO3) and realize reversible resistivity modulation. Under positive gate voltage, the resistivity of SmNiO3 exhibits a colossal increase upon the Zn2+ intercalation and the concurrent electron doping. Under negative gate voltage, the Zn2+ ions are extracted and the resistivity decreases significantly. The resistivity modulation using Zn2+ is non-volatile. Electrochromic behavior is also observed during the Zn2+ insertion and extraction. The electronic phase transition is charac-terized using various techniques. Moreover, the trivalent Al3+ ions are also investigated as charge carriers to modulate the resistivity of SmNiO3 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 SmNiO3 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 SmNiO3 with the use of high-valence cations under applied voltage, underscoring the potential for applications in novel emerging electronic devices.