Gated negative-effective-mass ballistic terahertz generators

We consider gate control of terahertz generation in planar ballistic diodes with a negative-effective-mass section in a dispersion relation of current carriers in a current-conducting channel. Such a generation in ballistic p (+) pp(+) or n(+) nn(+) diodes occurs as a result of plasma instability dev elopment and self-organization of a regular oscillation regime. Conditions of existence and oscillation frequencies are calculated. The gate can also serve as an oscillation-collecting electrode. We consider double-gate desig ns, side by side with conventional single-gate designs. The double-gate dev ices allow us to separate circuits for direct and high-frequency currents. (C) 1999 American Institute of Physics. [S0003-6951(99)00141-2].