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تسجيل مستخدم جديدElectrostatic gating of metallic and insulating phases in SmNiO3 ultrathin films
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The correlated electron system SmNiO3 exhibits a metal-insulator phase transition at 130 {deg}C. Using an ionic liquid as an electric double layer (EDL) gate on three-terminal ultrathin SmNiO3 devices, we investigate gate control of the channel resistance and transition temperature. Resistance reduction is observed across both insulating and metallic phases with ~25% modulation at room temperature. We show that resistance modulation is predominantly due to electrostatic charge accumulation and not electrochemical doping by control experiments in inert and air en-vironments. We model the resistance behavior and estimate the accumulated sheet density (~1-2 x 10^14 cm^-2) and EDL capacitance (~12 {mu}F/cm^2).
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