Physicists from the University of Science and Technology of Missouri, the University of Yale and the University of Grenoble Alpa recently conducted a study involving large-scale modeling of light propagation in complex 3D structures. Their findings, published in Physical Review Letters, have affirmed that the Anderson phase transition for light mirrors similar transitions observed in electrons, sound waves, and other vibrations propagating through random media.
The concept of Anderson’s transition illustrates a scenario where waves stop diffusing and instead become localized, confined to specific areas. Originally described by physicist Philip Anderson in the context of electrons within disordered solid materials, it was later recognized as a universal phenomenon across various wave types.
In this new research, the focus was on light waves, with researchers modeling their behavior within ensembles of intersecting spheres made of perfectly conducting material. To address challenges usually encountered in observing phase transitions within complex systems, the scientists utilized a scaling approach towards the system’s final size. This methodology revealed a distinct critical frequency threshold at which the system shifts from diffuse behavior to a state of localization.
A pivotal part of this investigation was the utilization of the Tidy3D computing platform by Flexcompute Inc., enabling simulations of electromagnetic wave behaviors in extensive 3D structures. Analysis indicated that the Anderson transition for light follows the same universal principles observed in metallic and mechanical systems. The researchers calculated a critical exponent around 1.5, indicative of a transition to the orthogonal universal class.
These findings have potential implications for advancements in optical technologies, offering possibilities for developing devices utilizing light localization effects. This could lead to the creation of new types of lasers, sensors, and nanoporous metallic structures. However, further validation is required through experiments with actual materials, necessitating work within the infrared and microwave spectra to minimize light absorption by metals.