Semiconductor superlattice

The work studies the effects of temperature on drift velocity of the electrons in semiconductor superlattices in electric and tilted magnetic fields. It is shown that a thermal distribution of the electrons can counter­intuitively enhance the phenomena related to resonances between the Bloch and the cyclotron frequencies of electron motion in superlattices. In particular, the increase of temperature leads to more prominent resonant maxima in the dependence of drift velocity of electrons on the strength of an electric field.

Periodic external signal effect on the collective dynamics of charge in semiconductor superlattice is studied. It is shown, that periodically­oscillating external electrical field can synchronize the transport of domains of the high density of charge as well as oscillations of electrical current flowing through the superlattice.

Present research is focused on the dynamics of the perturbation of semiconductor superlattice (SL) reference state near the generation threshold as for the case of influence of titled magnetic field as for the case when the magnetic field is absent. The evolution of the considered perturbation is described with the help of linearized evolution operator. It has been shown that increase of the applied voltage leads to decrease of the attenuation coefficient, which becomes zero in bifurcation point where stationary state loses it’s stability.

In this letter we study nonlinear dynamics and transition to chaos in semiconductor superlattice coupled to external linear resonator. We have shown that such system demonstrates chaotic dynamics in wide range of supply voltage, whereas in autonomous superlattice only periodical dynamics exists. Revealed that transition to chaos in system goes through intermittency.