Observation of Chaotic Behavior in an Electron-Hole Plasma in Ge

Abstract

Spontaneous current oscillations which develop chaotic behavior are reported for an electron-hole plasma in a crystal of Ge at 77 K in parallel electric and magnetic fields. The observed behavior includes a period-doubling route to chaos with increasing applied electric field, regions of broadband noise which contain noise-free periodic windows, and bifurcations from quasiperiodic states to turbulence. A rate-equation model, which includes nonlinear coupling between unstable and damped plasma density waves, is presented.