The lock-on effect and collapsing bipolar Gunn domains in high-voltage GaAs avalanche p-n junction diode

We present experimental evidence and physics-based simulations of the lock-on effect in high-voltage GaAs avalanche diodes . The triggering is initiated by steep voltage ramp applied to diode in-series 50 ? load. After subnanosecond switching reversely biased remains conducting state for whole duration pulse (dozens nanoseconds). There no indication p-n junction recovery that commonly expected develop on nanosecond scale due drift extraction non-equilibrium carriers. keeps a constant value ?70 V much lower than stationary breakdown 400 V. Numerical reveal supported impact ionization narrow high-field collapsing Gunn domains as well quasi-stationary cathode anode ionizing domains. Collapsing spontaneously appear dense electron-hole plasma negative differential mobility electrons GaAs. resembles bulk photoconductive switches but observed switched non-optical method. • exhibit after switching. Ionizing support conductivity diode. bipolar channels at high current density. Chaotic dynamics results sub-THz emission.