Superlattice GaAs mixed tunneling avalanche transit time device structure

Abstract

A superlattice GaAs-Ga0.7Al0.3As mixed tunneling avalanche transit time device has been fabricated and tested at 94 GHz. Two superlattice regions are utilized in order to control the avalanche and the drift currents. The superlattice in the avalanche region enhances the electron ionization rate by a factor of 8, while the superlattice in the drift region maximizes the tunneling current. At 94 GHz, pulsed output power of 0.2–0.4 W was obtained.

Frequency and amplitude modulation of ultra-compact terahertz quantum cascade lasers using an integrated avalanche diode oscillator

“…A microwave oscillator is integrated into the QCL cavity in order to produce a time-dependent modulation of the optical gain. GaAs-based microwave oscillators have previously been shown to emit radiation up to 150 GHz by exploiting the negative differential resistance of avalanche-based diodes 19 20 21 22 . By engineering a THz frequency QCL in a double-metal waveguide with an integrated GaAs-based tunable avalanche oscillator, we report observation of the emission of frequency and amplitude modulated THz radiation.…”