Park, Haedong Jo, Seungyun Kang, Byungsoo Hur, Kahyun Oh, Sang Soon Ryu, Du Yeol Lee, Seungwoo 2024-01-19T12:03:18Z 2024-01-19T12:03:18Z 2022-04-05 2022-05 2192-8606 https://pubs.kist.re.kr/handle/201004/115250 A gyroid crystal possesses a peculiar structural feature that can be conceptualized as a triply periodic surface with a constant mean curvature of zero. The exotic optical properties such as the photonic bandgap and optical chirality can emerge from this three-dimensional (3D) morphological feature. As such, gyroid crystals have been considered as the promising structures for photonic crystals and optical metamaterials. To date, several methods have been proposed to materialize gyroid crystals, including 3D printing, layer-by-layer stacking, two-photon lithography, interference lithography, and self-assembly. Furthermore, the discovery of Weyl points in gyroid crystals has further stimulated these advancements. Among such methods, the self-assembly of block copolymers (BCPs) is unique, because this soft approach can provide an easy-to-craft gyroid, especially at the nanoscale. The unit-cell scale of a gyroid ranging within 30-300 nm can be effectively addressed by BCP self-assembly, whereas other methods would be challenging to achieve this size range. Therefore, a BCP gyroid has provided a material platform for metamaterials and photonic crystals functioning at optical frequencies. Currently, BCP gyroid nanophotonics is ready to take the next step toward topological photonics beyond the conventional photonic crystals and metamaterials. In particular, the intrinsic lattice transformations occurring during the self-assembly of BCP into a gyroid crystal could promise a compelling advantage for advancing Weyl photonics in the optical regime. Lattice transformations are routinely considered as limitations, but in this review, we argue that it is time to widen the scope of the lattice transformations for the future generation of nanophotonics. Thus, our review provides a comprehensive understanding of the gyroid crystal and its lattice transformations, the relevant optical properties, and the recent progress in BCP gyroid self-assembly. English WALTER DE GRUYTER GMBH Block copolymer gyroids for nanophotonics: significance of lattice transformations Article 10.1515/nanoph-2021-0644 1 Nanophotonics, v.11, no.11, pp.2583 - 2615 Nanophotonics 11 11 2583 2615 Y scie scopus 000743648100001 2-s2.0-85123999576 Nanoscience & Nanotechnology Materials Science, Multidisciplinary Optics Physics, Applied Science & Technology - Other Topics Materials Science Optics Physics Review DIRECTIONAL PHOTOFLUIDIZATION LITHOGRAPHY BUTTERFLY WING SCALES PHOTONIC BAND-GAPS THIN-FILMS WEYL POINTS INTERFERENCE LITHOGRAPHY MULTIBEAM INTERFERENCE 2-PHOTON LITHOGRAPHY OPTICAL-PROPERTIES REFRACTIVE-INDEX block copolymers chirality gyroids optical metamaterials Weyl points