title: Metadisorder for designer light in random systems.
abstract: Disorder plays a critical role in signal transport by controlling the correlation of a system, as demonstrated in various complex networks. In wave physics, disordered potentials suppress wave transport, because of their localized eigenstates, from the interference between multiple scattering paths. Although the variation of localization with tunable disorder has been intensively studied as a bridge between ordered and disordered media, the general trend of disorder-enhanced localization has remained unchanged, and the existence of complete delocalization in highly disordered potentials has not been explored. We propose the concept of "metadisorder": randomly coupled optical systems in which eigenstates can be engineered to achieve unusual localization. We demonstrate that one of the eigenstates in a randomly coupled system can always be arbitrarily molded, regardless of the degree of disorder, by adjusting the self-energy of each element. Ordered waves with the desired form are then achieved in randomly coupled systems, including plane waves and globally collective resonances. We also devise counterintuitive functionalities in disordered systems, such as "small-world-like" transport from non-Anderson-type localization, phase-conserving disorder, and phase-controlled beam steering.
authors.affiliation: Photonic Systems Laboratory, Department of Electrical and Computer Engineering, Seoul National University, Seoul 08826, Korea.
authors.forename: Sunkyu
authors.identifier: 0000-0001-8667-6404
authors.initials: S
authors.lastname: Yu
authors.affiliation: Photonic Systems Laboratory, Department of Electrical and Computer Engineering, Seoul National University, Seoul 08826, Korea.
authors.forename: Xianji
authors.initials: X
authors.lastname: Piao
authors.affiliation: Photonic Systems Laboratory, Department of Electrical and Computer Engineering, Seoul National University, Seoul 08826, Korea.
authors.forename: Jiho
authors.initials: J
authors.lastname: Hong
authors.affiliation: Photonic Systems Laboratory, Department of Electrical and Computer Engineering, Seoul National University, Seoul 08826, Korea.
authors.forename: Namkyoo
authors.identifier: 0000-0003-0197-7633
authors.initials: N
authors.lastname: Park
keywords: Anderson localization; Disorder; beam steering; chirality; invisibility; metamaterial; network; orbital angular momentum; random-walk potential; wave transport