Noise enhanced spontaneous chaos in semiconductor superlattices at room temperature

Abstract

Physical systems exhibiting fast spontaneous chaotic oscillations are used to generate high-quality true random sequences in random number generators. The concept of using fast practical entropy sources to produce true random sequences is crucial to make storage and transfer of data more secure at very high speeds. While the first high-speed devices were chaotic semiconductor lasers, the discovery of spontaneous chaos in semiconductor superlattices at room temperature provides a valuable nanotechnology alternative. Spontaneous chaos was observed in 1996 experiments at temperatures below liquid nitrogen. Here we show spontaneous chaos at room temperature appears in idealized superlattices for voltage ranges where sharp transitions between different oscillation modes occur. Internal and external noises broaden these voltage ranges and enhance the sensitivity to initial conditions in the superlattice snail-shaped chaotic attractor thereby rendering spontaneous chaos more robust.

6 pages, 4 figures, revtex

References in corpus (3)

• A hybrid model for chaotic front dynamics: From semiconductors to water tanks
• Voltage switching and domain relocation in semiconductor superlattices
• Theory of charge fluctuations and domain relocation times in semiconductor superlattices

Cited by in corpus (6)

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• Noise-enhanced chaos in a weakly coupled GaAs/(Al,Ga)As superlattice
• Designing hyperchaos and intermittency in semiconductor superlattices
• Enhancing Chaotic Behavior at room temperature in GaAs/(Al,Ga)As Superlattices
• Scaling properties of noise-induced switching in a bistable tunnel diode circuit
• Hyperchaos, intermittency, noise and disorder in modified semiconductor superlattices