Theoretical Criteria for Scattering Dark States in Nanostructured Particles

• Published in: Nano letters Vol. 14; no. 5; pp. 2783 - 2788
• Main Authors: Hsu, Chia Wei, DeLacy, Brendan G, Johnson, Steven G, Joannopoulos, John D, Soljačić, Marin
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 14.05.2014
• Subjects: Angular momentum; Channels; Condensed matter: structure, mechanical and thermal properties; Exact sciences and technology; Joining; Light scattering; Low-dimensional structures (superlattices, quantum well structures, multilayers): structure, and nonelectronic properties; Nanostructure; Physics; Resonance scattering; Scattering; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Temporal logic; coupled-resonator-induced transparency; Fano resonances; Scattering dark states; light scattering; nanostructures; temporal coupled-mode theory; Transparency; Light scattering; Interference; Far field; Momentum; Resonance; Nanostructures; Resonators
• ISSN: 1530-6984; 1530-6992
• DOI: 10.1021/nl500340n

Nanostructures with multiple resonances can exhibit a suppressed or even completely eliminated scattering of light, called a scattering dark state. We describe this phenomenon with a general treatment of light scattering from a multiresonant nanostructure that is spherical or nonspherical but subwavelength in size. With multiple resonances in the same channel (i.e., same angular momentum and polarization), coherent interference always leads to scattering dark states in the low-absorption limit, regardless of the system details. The coupling between resonances is inevitable and can be interpreted as arising from far-field or near-field. This is a realization of coupled-resonator-induced transparency in the context of light scattering, which is related to but different from Fano resonances. Explicit examples are given to illustrate these concepts.