High-frequency modulation of bound-to-continuum Terahertz quantum cascade lasers up to 24GHz

We report on the high frequency modulation of terahertz (THz) quantum cascade lasers (QCLs). By resonantly enhancing the frequency response of the RF biasing circuit we show that 4 mm and 1.5 mm-long metal-metal waveguide 2.3 THz QCLs, can be modulated up to 21 and 24 GHz respectively.