Compact ferroelectric domain-ensemble model linking PUND switching, wake-up, and plasmonic optical readout

We develop a compact ferroelectric "digital twin" that links electrical switching, long-term wake-up, and plasmon-enhanced optical read-out in a single framework. The ferroelectric layer is represented as an ensemble of bistable domains that switch thermally over a Weibull-distributed energy barrier. The macroscopic response combines this domain engine with a Rayleigh-type nonlinear background, a fixed series capacitance that captures depletion/interface effects, and a parallel ohmic leakage path. These static parameters are calibrated once to a 1 kHz positive-up negative-down (PUND) data set, reproducing the full switching-current waveforms and centred P-V branches with consistent P_s, P_r, and E_c. Keeping the calibrated engine fixed, we then (i) introduce a minimal frequency-dependent leakage factor that accounts for the substantial increase in apparent polarization at low frequencies (100-1 Hz), and (ii) describe wake-up over 10³ cycles with a two-component stretched-exponential law that separates fast and slow relaxation. Finally, the simulated polarization is coupled to a plasmonic cavity by a nonlinear, time-lagged interpolation between two remnant and saturated states. This yields realistic wavelength-resolved modulation that requires no additional optical fitting, demonstrating that a single electrical calibration is sufficient to predict full device-level ferroelectric dynamics and their plasmonic signatures. In turn, this provides an alternate pathway for using optical, rather than electrical, signals as a readout method in ferroelectric devices.