Hizanidis J, Balanov A, Amann A, Schöll E
Institut für Theoretische Physik, Technische Universität Berlin, Hardenbergstrasse 36, 10623 Berlin, Germany.
Phys Rev Lett. 2006 Jun 23;96(24):244104. doi: 10.1103/PhysRevLett.96.244104.
We show that front motion can be induced by noise in a spatially extended excitable system with a global constraint. Our model system is a semiconductor superlattice exhibiting complex dynamics of electron accumulation and depletion fronts. The presence of noise induces a global change in the dynamics of the system forcing stationary fronts to move through the entire device. We demonstrate the effect of coherence resonance in our model; i.e., there is an optimal level of noise at which the regularity of front motion is enhanced. Physical insight is provided by relating the space-time dynamics of the fronts with a phase-space analysis.
我们表明，在具有全局约束的空间扩展可激发系统中，噪声可诱导前沿运动。我们的模型系统是一个半导体超晶格，展现出电子积累和耗尽前沿的复杂动力学。噪声的存在会引起系统动力学的全局变化，迫使静止前沿在整个器件中移动。我们在模型中展示了相干共振效应；即存在一个最优噪声水平，在此水平下前沿运动的规律性会增强。通过将前沿的时空动力学与相空间分析相关联，提供了物理见解。
