Fig. 2: THz field-driven lattice phonon oscillations in frequency domain.
From: Terahertz displacive excitation of a coherent Raman-active phonon in V2O3
a Normalized spectral amplitude (Norm. sp. ampl.) of the THz pump pulse in Fig. 1d (green solid curve) and same spectrum with 2x frequency (green dashed curve). b Fourier transform of the oscillatory component of ΔT/T for tpp > 0.4 ps (blue curve). c Raman spectroscopy of V2O3 thin film at 300 K. Light blue dots are experimental data and light solid curve is the fit curve, which contains different spectral components: two Eg modes and the A1g. The red curve is lineshape of the A1g phonon, which is peaked at 7.1 THz. Vertical offset of -0.5 has been added to the experimental data for the overlap with the A1g phonon lineshape. Data without offset is shown in Supplementary Fig. 4 and discussed in Supplementary Note 3. d Normalized oscillations amplitude (Norm. osc. ampl.) vs the normalized (Norm.) THz field strength, E0/Epeak, with Epeak = 6.5 MV/cm. The amplitude scales quadratically with the pump electric field (the light blue solid line represents a quadratic fit). Error bars indicate the standard deviations of the mean determined from pump-probe scan measurements with 15 acquisitions per point.
