The discovery of topological phases has recently led to a paradigm shift in condensed matter physics, and facilitated breakthroughs in engineered photonics and acoustic metamaterials. Topological insulators (TIs) enable the generation of electronic, photonic, and acoustic modes exhibiting wave propagation that is resilient to disorder, irrespective of manufacturing precision or unpredictable defects induced by the operational environment, known as topological protection. While originally limited to a dimensionality of the protected states that is one dimension lower than the host TI material, the recent discovery of higher-order topological insulators (HOTIs) provides the potential to overcome this dimensionality limitations by offering topological protection over an extended range of dimensionalities. Here we demonstrate 2D photonic HOTI (PHOTI) with topological states two dimensions lower than the one of the host system. We consider a photonic metacrystal of distorted Kagome lattice geometry that exhibits topological bulk polarization, leading to the emergence of 1D topological edge states and of higher order 0D states confined to the corners of the structure. Interestingly, in addition to corner states due to the nearest neighbour interactions and protected by generalized chiral symmetry 1 , we discover and take advantage of a new class of topological corner states sustained by long-range interactions, available in wave-based systems, such as in photonics. Our findings demonstrate that photonic HOTIs possess richer physics compared to their condensed matter counterparts, offering opportunities for engineering novel designer electromagnetic states with unique topological robustness.Main text: Topological systems exhibit unique and often counterintuitive properties, such as robust electronic transport and wave propagation, which promise to revolutionizing technologies across different fields, from quantum electronics and quantum photonics, topological phenomena unlocked novel approaches for quantum computing interfaces 32, 33 and robust lasing 34,35,36 , while in a broad range of classical fields, including optics, mechanics and acoustics, they offer an unprecedented degree of control via synthetic degrees of freedom and robustness, which manifests itself as resilience to defects and disorder 11While most topological systems studied so far have been characterized by the presence of topological states with dimensionality one order lower than the one of the system, recently a new class of topological systems, so called higher-order topological insulators (HOTIs), have been introduced 38,39,40,41 . As opposed to conventional topological insulators, HOTIs support topological states 39,40,42,43,44,45,46,47 two and more dimensions lower than the system itself, referred to as higher-order topological (HOT) states. One example of such systems is given by quadrupole topological insulators 38,48 , which have been recently implemented in mechanical 49
The routing of light in a deep subwavelength regime enables a variety of important applications in photonics, quantum information technologies, imaging and biosensing. Here we describe and experimentally demonstrate the selective excitation of spatially confined, subwavelength electromagnetic modes in anisotropic metamaterials with hyperbolic dispersion. A localized, circularly polarized emitter placed at the boundary of a hyperbolic metamaterial is shown to excite extraordinary waves propagating in a prescribed direction controlled by the polarization handedness. Thus, a metamaterial slab acts as an extremely broadband, nearly ideal polarization beam splitter for circularly polarized light. We perform a proof of concept experiment with a uniaxial hyperbolic metamaterial at radio-frequencies revealing the directional routing effect and strong subwavelength l/300 confinement. The proposed concept of metamaterial-based subwavelength interconnection and polarizationcontrolled signal routing is based on the photonic spin Hall effect and may serve as an ultimate platform for either conventional or quantum electromagnetic signal processing.
Resonant slot nanoantennas for surface plasmon radiation in optical frequency range Appl. Phys. Lett. 100, 241115 (2012); 10.1063/1.4729552Experimental realization of all-dielectric composite cubes/rods left-handed metamaterial
We study the interplay between collective and individual optically-induced magnetic responses in quadrumers made of identical dielectric nanoparticles. Unlike their plasmonic counterparts, all-dielectric nanoparticle clusters are shown to exhibit multiple dimensions of resonant magnetic responses that can be employed for the realization of anomalous scattering signatures. We focus our analysis on symmetric quadrumers made from silicon nanoparticles and verify our theoretical results in proof-of-concept radio frequency experiments demonstrating the existence of a novel type of magnetic Fano resonance in nanophotonics. * ben.hopkins@anu.edu.au 1 arXiv:1607.04592v1 [physics.optics]
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.