Bifurcations and the transition to chaos in the resonant-tunneling diode

Recent experiments by Muller et al. [Phys. Rev. Lett. 75, 2875 (1995)] and Boebinger et al. [Surf. Sci. 361-362, 742 (1996)] investigated the transition to chaos and the effects of bifurcations on the magnetotunneling spectrum of a quantum well in tilted fields. We introduce a computationally efficient model for the device which successfully reproduces the main features of the experiments. We find that a number of separate dynamical regimes in the experiment at theta=11 degrees are each characterized by a distinctive experimental spectral profile. We use this signature to identify a period doubling resonance and tangent bifurcation but find that the second observed period doubling in the tunneling current is not due to a bifurcation.