Desktop megawatt superradiant free-electron laser at terahertz frequencies

I present a theoretical and simulation study of a desktop, megawatt (MW), terahertz (THz) superradiance free-electron laser (FEL) driven by a THz-pulse-train photoinjector. With nominal electron parameters from a THz-pulse-train photoinjector, this superradiant FEL is capable of generating more than 5 MW power at THz frequencies from a half-meter, single-pass undulator. Tapering the undulator to a length of 1.5 m can further increase the FEL output power to nearly 15 MW.