Fig. 3: Characteristics of THz generation by R-FWM in diamond.

a THz output energy versus resonance detuning. b Dependence of THz output energy with time relative to the vibration excitation Q(t) and its fit with |Q(t)|2. c Temporal trace of a THz pulse with PM at 5 THz measured by EOS in GaP. d Amplitude and phase spectra from Fourier transform of the THz pulse in (c). e THz pulses with CEP of 0 (red curve) and π (blue curve). f Measurement (scatters) and fitting (solid curve) of polarization distribution of 17 THz output showing that the THz pulses were linearly polarized