Harnessing intrinsic localized modes to identify impurities in nonlinear periodic systems.

Autor: Thota, M., Harne, R. L., Wang, K. W.
Předmět:
Zdroj: Journal of Applied Physics; 2015, Vol. 117 Issue 7, p074505-1-074505-11, 11p, 2 Diagrams, 3 Charts, 8 Graphs
Abstrakt: Intrinsic localized modes (ILMs) are concentrations of vibrational energy in periodic systems/ lattices due to the combined influences of nonlinearity and discreteness. Moreover, ILMs can move within the system and may strongly interact with an impurity, such as a stiffness change, mass variation, etc. Numerous scientific fields have uncovered examples and evidence of ILMs, motivating a multidisciplinary pursuit to rigorously understand the underlying principles. In spite of the diverse technical studies, a characterization of ILM interaction behaviors with multiple impurities in dissipative lattices remains outstanding. The insights on such behaviors may be broadly useful when dynamic measurements are the only accessible features of the periodic system. For instance, one may guide an ILM within the lattice using a deliberately applied and steered impurity and harness the observed interaction behaviors with a second, static (immovable) impurity/defect to identify how the underlying lattice is different at the second, defected site, whether or not one knew the position of the defect a priori. In this spirit, this research studies, analyzes, and characterizes the interaction types amongst an ILM and multiple impurities, and devises a method to identify a static defect impurity using quantitatively and qualitatively distinct interaction phenomena. The method is found to be robust to moderate levels of lattice stiffness heterogeneity and is applicable to monitor various property changes that represent impurities. Finally, experimental studies verify that ILMs interact with multiple impurities in unique ways such that defect features may be effectively identified. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index