“…The frequency-dependent step-like dispersion curves of ε / are fitted with a modified Cole–Cole model. 24,29
where ε ∞ is the high frequencies permittivity, Δ ε is the difference between statics and high frequency electrical permittivity, τ is the average relaxation time, α is the Cole–Cole parameter (0 ≤ α ≤ 1), σ SP is the conduction due to space charge, and P is the frequency power term added due to electrical conduction contribution. The fitted data demonstrates that space charge polarization or interfacial polarization improves at the RESET potential compared to the SET and no bias condition (as Δ ε values increases from 58.4 to 86.1 and 112.7 at a SET, zero bias, and RESET condition) (shown in Table S5, ESI†).…”