Intrinsic bistability and emitter scattering in resonant tunneling diodes

Incoherent scattering degrades the peak-to-valley ratio in resonant tunneling diodes (RTDs). In addition, scattering reduces intrinsic bistability, which is a hysteresis in current–voltage (I–V) characteristics. Previous numerical calculations considered only incoherent scattering in the well. In this work, by a unified treatment of current flowing from emitter continuum states and emitter quasi-bound states, we study also the effect of emitter scattering on intrinsic bistability. An analytical model that retains the salient features of intrinsic bistability is given. It is shown numerically that: (a) broadening induced by incoherent scattering in the emitter reduces intrinsic bistability; and (b) emitter scattering is on same footing with well scattering. This result may explain the discrepancy between numerical simulators and experimental facts regarding the presence of intrinsic bistability in such devices like RTDs.