Electrically tunable GHz oscillations in doped GaAs-AlAs superlattices

Abstract

Tunable oscillatory modes of electric-field domains in doped semiconductor superlattices are reported. The experimental investigations demonstrate the realization of tunable, GHz frequencies in GaAs-AlAs superlattices covering the temperature region from 5 to 300 K. The orgin of the tunable oscillatory modes is determined using an analytical and a numerical modeling of the dynamics of domain formation. Three different oscillatory modes are found. Their presence depends on the actual shape of the drift velocity curve, the doping density, the boundary condition, and the length of the superlattice. For most bias regions, the self-sustained oscillations are due to the formation, motion, and recycling of the domain boundary inside the superlattice. For some biases, the strengths of the low and high field domain change periodically in time with the domain boundary being pinned within a few quantum wells. The dependency of the frequency on the coupling leads to the prediction of a new type of tunable GHz oscillator based on semiconductor superlattices.

Tex file (20 pages) and 16 postscript figures

References in corpus (4)

• Dynamics of Electric Field Domains and Oscillations of the Photocurrent in a Simple Superlattice Model
• Chaos in resonant-tunneling superlattices
• Current-voltage characteristic and stability in resonant-tunneling n-doped semiconductor superlattices
• Chaotic dynamics of electric-field domains in periodically driven superlattices

Cited by in corpus (28)

• Photon-assisted transport in semiconductor nanostructures
• Semiconductor Superlattices: A model system for nonlinear transport
• Current-voltage characteristic and stability in resonant-tunneling n-doped semiconductor superlattices
• Controlling and enhancing THz collective electron dynamics in superlattices by chaos-assisted miniband transport
• Chaotic front dynamics in semiconductor superlattices
• Microscopic derivation of transport coefficients and boundary conditions in discrete drift-diffusion models of weakly coupled superlattices
• Current self-oscillations, spikes and crossover between charge monopole and dipole waves in semiconductor superlattices
• Wavefronts may move upstream in doped semiconductor superlattices
• Sequential tunneling in doped superlattices: Fingerprints of impurity bands and photon-assisted tunneling
• Kondo effect and bistability in a double-quantum-dot
• Impurity bands and sequential resonant tunneling in the presence of terahertz fields
• Voltage switching and domain relocation in semiconductor superlattices
• Quasiperiodic time dependent current in driven superlattices: distorted Poincare maps and strange attractors
• Motion of Wavefronts in Semiconductor Superlattices
• Spin-polarized current oscillations in diluted magnetic semiconductor multiple quantum wells
• Limit cycle induced frequency locking in self-sustained current oscillations of superlattices
• Asymptotic analysis of the Gunn effect with realistic boundary conditions
• Temperature dependence of current self-oscillations and electric field domains in sequential tunneling doped superlattices
• Nonlinear stochastic discrete drift-diffusion theory of charge fluctuations and domain relocation times in semiconductor superlattices
• Two mini-band model for self-sustained oscillations of the current through resonant tunneling semiconductor superlattices
• Universality of the Gunn effect: self-sustained oscillations mediated by solitary waves
• Stationary states and phase diagram for a model of the Gunn effect under realistic boundary conditions
• Tristability in a non-equilibrium double-quantum-dot in Kondo regime
• Parameter dependence of high-frequency nonlinear oscillations and intrinsic chaos in short GaAs/(Al,Ga)As superlattices
• Kondo effect in a double quantum-dot molecule under the effect of an electric and magnetic field
• Photoassisted dynamical transport in multiple quantum wells
• Pulse propagation in discrete systems of coupled excitable cells
• Periodic generation and propagation of traveling fronts in dc voltage biased semiconductor superlattices