Mode-locking of self-generated oscillations in a semiconductor model for low-temperature impurity breakdown

Research paper by H. Naber, E. Schöll

Indexed on: 01 Jun '90Published on: 01 Jun '90Published in: Zeitschrift für Physik B Condensed Matter


The nonlinear dynamic behaviour of a model for self-generated, spatially coupled current oscillations in two separated parts of a semiconductor is analysed. The model involves impurity impact ionization, nonlinear energy relaxation of hot carriers, and energy exchange between the two subsystems. Quasiperiodicity and mode-locking are obtained, and characterized by a suitably defined rotation number and a spectral bifurcation diagram. The mode-locking structure is found to obey the Farey tree ordering, and can be understood on the basis of the circle map theory, assuming a particular path in the two-dimensional phase diagram of the circle map.