Control of THz pulse emission in laser plasma interaction by plasma shaping

High-energy, few-cycle THz pulse generation by high-intensity (∼10 18 W/cm 2 ) femtosecond laser with plasma mirrors have received significant attention in recent years [1-3]. This novel THz source has the potential of generating large bandwidth millijoule pulse energies, opening up applications in THz nonlinear optics, single-shot imaging and spectroscopy [4]. Solid density plasma shaping has already been observed [5, 6] to yield sub-cycle control in optimizing high harmonic generation from plasma mirrors. Here, we demonstrate that plasma shaping can be a prospective avenue for enhancing and controlling THz emission from plasma mirrors. In this study, we have used two different cases of plasma shaping.