Fig. 4: Second harmonic modulation by CD electrical stimuli.

a Spectrum of the reflected signal from the sample with FF = 0.3 and α = 0.19 (see also the Supplementary Information, section S6 for the sample with FF = 0.5). b Normalized SHG excitation spectrum, obtained by sweeping the wavelength of the fundamental beam with a constant optical intensity on the sample of 12 kW/cm2. c–f EO modulation of SHG, excited with four different wavelengths (identified by vertical dashed lines in a, b depending on the applied DC voltage VDC.