Operation of resonant-tunnelling-diode oscillators beyond tunnel-lifetime limit at 564 GHz

Abstract

We present resonant-tunnelling-diode (RTD) oscillators, which are operating at frequencies up to 564 GHz. Due to heavy doping of the collector side of our diodes, the oscillators are operating beyond the tunnel-lifetime (τ) and relaxation-time (τrel) limits of RTDs. At 564 GHz we achieve ωτ≈1.2 and ωτrel≈2.6, the highest previously reported value of ωτ at frequencies >150 GHz was ≈0.6. Our study indicates that operating frequencies of RTD oscillators could be significantly increased and RTDs should be capable of operating at frequencies of several THz.