Carpio A, Bonilla L L, Luzón A
Departamento de Matemática Aplicada, Universidad Complutense de Madrid, 28040 Madrid, Spain.
Phys Rev E Stat Nonlin Soft Matter Phys. 2002 Mar;65(3 Pt 2A):035207. doi: 10.1103/PhysRevE.65.035207. Epub 2002 Mar 1.
Pinning and depinning of wave fronts are ubiquitous features of spatially discrete systems describing a host of phenomena in physics, biology, etc. A large class of discrete systems is described by overdamped chains of nonlinear oscillators with nearest-neighbor coupling and subject to random external forces. The presence of weak randomness shrinks the pinning interval and it changes the critical exponent of the wave front depinning transition from 1/2 to 3/2. This effect is derived by means of a recent asymptotic theory of the depinning transition, extended to discrete drift-diffusion models of transport in semiconductor superlattices and is confirmed by numerical calculations.
波前的钉扎和解钉扎是空间离散系统中普遍存在的特征，描述了物理学、生物学等领域的许多现象。一大类离散系统由具有最近邻耦合且受随机外力作用的过阻尼非线性振荡器链来描述。弱随机性的存在会缩小钉扎区间，并使波前解钉扎转变的临界指数从1/2变为3/2。这种效应是通过最近的解钉扎转变渐近理论推导出来的，该理论已扩展到半导体超晶格中输运的离散漂移扩散模型，并通过数值计算得到了证实。
