Abstract

Oscillators using resonant tunneling through a quantum well have been the focus of much research recently [1-4]. Although they are potentially capable of very high frequency operation with low noise, the output power is in the order of tens of microwatts. Transit time devices like the IMPATT (impact ionization avalanche transit time) are capable of operating at 94 GHz and 140 GHz with 0.5 and 0.12 W power output respectively [5,6]. But collision effects in transit time devices seriously degrade the power and efficiency beyond 90 GHz and result in poor noise characteristics. Tunneling in the TUNNETT (tunnel injection and transit time) was proposed as a low noise alternative to the IMPATT, but poor injection phase delay lowers the efficiency of operation [7,8].

© 1987 Optical Society of America