Powerful THz Emission from Laser Wakefields in Inhomogeneous Magnetized Plasmas

Powerful coherent terahertz (THz) pulse with a broad spectrum (0.5-3 THz) can be produced from a laser-driven wakefield through linear mode conversion in inhomogeneous magnetized plasmas with maximum plasma density of 10¹⁷ cm^-3. The external dc magnetic field is a few tesla (T). Such wakefield emission can be a powerful THz source at MW level and capable of affording field strength of a few MV/cm, suitable for THz nonlinear physics. These THz emissions are always with a positive chirp, through a proper dispersion compression, a single-cycle THz pulse with higher peak field strength can be generated.