Controlled shifting of carrier-envelope phase of broadband terahertz pulses using prism wave plates

A carrier-envelope phase (CEP) shifter for broadband terahertz (THz) pulses was demonstrated. The CEP, the phase of the carrier frequency with respect to the peak of the THz pulses, is a key element in light-matter interactions in high fields, especially when few-cycle pulses are used. The CEP shifter was constructed by suitably arranging several prism wave plates. By rotating the wave plates, we could control both the CEP and the polarization angle of the THz pulses.