Steady states of a microwave-irradiated modulation-doped heterostructure under perpendicular magnetic field

We present a theoretical model and study dynamics of the modulation-doped GaAs/AlxGa1−xAs heterostructure under a perpendicular magnetic field and microwave radiation. We propose a mechanism, which is based on the nonlinear dynamics of real-space electron transfer and delayed dielectric relaxation of the interface potential barrier resulting from the space charge in the doped AlGaAs layer. Static analysis specifies the negative differential conductance region when the dc bias voltage varies. The self-sustained oscillations and bistability between oscillationary and stationary states are predicted. Varying with the microwave irradiation amplitude and the perpendicular magnetic field, the routes from period-doubling to chaos, quasiperiodicity, and frequency-locking are found. In addition varying with the microwave irradiation frequency can lead to time-independent homogeneous steady states spatially and result in a longitudinal resistance oscillation with period tuned by the ratio of microwave radiation frequency ω to the cyclotron frequency ωc and local minima at ω/ωc=integer+1/4.