Fig. 3: Antiferroelectric and ferroelectric behaviour of the 200-nm-thick NNO films.
From: Ultrahigh electromechanical response from competing ferroic orders
a, Electric-field-dependent polarization curves of the NNO film. The inset shows the remnant polarization as a function of the applied electric field. b, Dynamic ferroelectric hysteresis loop and corresponding switching current curve of the NNO film. c, Simulation of the ferroelectric hysteresis loop of FE and AFE coexistence with a ratio of 1:3 based on Landau theory. d–f, PFM images of topography (d), amplitude (e) and phase (f) measured after writing the FE domain. a.u., arbitrary units. Scale bar, 2 μm (d,e,f).
