Extended Data Fig. 2: Decay of the NOTE signal at large tip-tapping amplitudes.
From: All-optical subcycle microscopy on atomic length scales
a, Electro-optically detected scattered THz transients demodulated at the second harmonic of the tip-tapping frequency (\({E}_{2}^{{\rm{scat}}}\)) with A = 5 nm and \({\hat{E}}_{{\rm{light}}}=1.1\) kV cm−1. For the transient acquired at the closest tip-sample distance \(\langle \,{J}_{{\rm{lw}}}\,\rangle =-180\) pA, on average about 80 rectified electrons per pulse. b, Peak of the THz transient (\({\hat{E}}_{2}^{{\rm{scat}}}\)) at t = 0 fs, measured at a tip-tapping amplitude A = 5 nm for increasing tip-sample separation \(\Delta z\). c, Logarithmic-scale plot of the data shown in Fig. 2b: \({\hat{E}}_{2}^{{\rm{scat}}}\) measured at the second harmonic of the tip-tapping frequency (A = 200 pm, \({\hat{E}}_{{\rm{light}}}=0.8\) kV cm−1), alongside the time-integrated lightwave tunnelling current \(\langle \,{J}_{{\rm{lw}}}\,\rangle \) measured for increasing tip-sample separation (on average about 200 electrons per pulse are rectified for the closest tip-sample distance).
