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Updated: Jun 25, 2026
15:58
Measurement of Coherence Decay in GaMnAs Using Femtosecond Four-wave Mixing
Published on: December 3, 2013
Control of coherence resonance in semiconductor superlattices
Johanne Hizanidis1, Eckehard Schöll
1Instutut für Theoretische Physik, Technische Universität Berlin, Hardenbergstasse 36, D-10623 Berlin, Germany.
Summary
Time-delayed feedback control can enhance or suppress coherence resonance in semiconductor superlattices. This method significantly boosts the coherence of charge motion, offering new control over spatiotemporal dynamics.
Area of Science:
- Condensed matter physics
- Nonlinear dynamics
- Semiconductor physics
Background:
- Semiconductor superlattices exhibit complex spatiotemporal charge dynamics.
- Deterministic dynamics near a saddle-node bifurcation on a limit cycle are sensitive to perturbations.
- Coherence resonance, noise-induced order, is observed in such systems.
Purpose of the Study:
- Investigate the impact of time-delayed feedback control on charge dynamics.
- Analyze the interplay between noise and feedback in semiconductor superlattices.
- Explore delay-induced dynamics and bifurcations.
Main Methods:
- Numerical simulation of spatiotemporal charge dynamics.
- Application of time-delayed feedback control.
- Analysis of saddle-node and homoclinic bifurcations.
- Study of coherence resonance phenomena.
Main Results:
- Time-delayed feedback can selectively enhance or destroy coherence resonance.
- Increased coherence of stochastic domain motion at low noise intensity was achieved.
- Purely delay-induced dynamics revealed a homoclinic bifurcation of a limit cycle.
Conclusions:
- Time-delayed feedback offers a powerful tool to control stochastic dynamics in semiconductor superlattices.
- The findings provide insights into noise-induced phenomena and nonlinear control.
- New routes to manipulate charge transport in nanodevices are suggested.
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