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Related papers: Topology-optimized Dual-Polarization Dirac Cones

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We propose a new design on integrated optical devices on-chip with an extra width degree of freedom by using a photonic crystal waveguide with Dirac points between two photonic crystals with opposite valley Chern numbers. With such an extra…

Optics · Physics 2023-09-19 Sai Yan , Jingnan Yang , Shushu Shi , Zhanchun Zuo , Can Wang , Xiulai Xu

Reconfigurable intelligent metasurfaces have been proposed as an efficient solution for improving wireless telecommunication systems in multiple scattering or reverberating media. Concurrently, topology optimization has been successfully…

Applied Physics · Physics 2023-11-07 Theodosios D. Karamanos , Mathias Fink , Fabrice Lemoult

Topological photonic insulators show promise for applications in compact integrated photonic circuits due to their ability to transport light robustly through sharp bendings. The number of topological edge states relies on the difference…

Applied Physics · Physics 2024-01-19 Weiyuan Tang , Mudi Wang , Shaojie Ma , C. T. Chan , Shuang Zhang

The field of topological photonics emerged as one of the most promising areas for applications in transformative technologies: possible applications are in topological lasers or quantum optics interfaces. Nevertheless, efficient and simple…

We present an all-dielectric photonic crystal structure that supports two-dimensionally confined helical topological edge states. The topological properties of the system are controlled by the crystal parameters. An interface between two…

We review the contributions of surface science methods to discover and improve 3D topological insulator materials, while illustrating with examples from our own work. In particular, we demonstrate that spin-polarized angular-resolved…

Controlling the charge carrier density provides an efficient way to trigger phase transitions and modulate the optoelectronic properties in natural materials. This approach could be used to induce topological transitions in the optical…

We design germanium-based higher-order topological cavities for terahertz applications by breaking the symmetry of a two-dimensional photonic crystal following the Su-Schrieffer-Heeger model. Calculations demonstrate the parity inversion of…

Applied Physics · Physics 2024-02-27 Ian Colombo , Pietro Minazzi , Emiliano Bonera , Fabio Pezzoli , Jacopo Pedrini

We show that two-dimensional phononic crystals exhibit Dirac cone dispersion at k=0 by exploiting dipole and quadrupole accidental degeneracy. While the equi-frequency surface of Dirac cone modes is isotropic, such systems exhibit…

Materials Science · Physics 2015-05-28 Fengming Liu , Yun Lai , Xueqin Huang , C. T. Chan

The polarizations of topological edge modes in the vicinity of optical Weyl points were numerically studied in chiral photonic crystals. We investigated two kinds of rotationally stacked woodpile structures in which planar rod arrays were…

Optics · Physics 2018-11-30 S. Takahashi , S. Oono , S. Iwamoto , Y. Hatsugai , Y. Arakawa

Photonic crystals (PCs) are periodic dielectric structures that severed as an excellent platform to manipulate light. A conventional way to guide/trap light via PCs is to introduce a line or point defect by removing or modifying several…

Optics · Physics 2024-01-26 Zi-Mei Zhan , Peng-Yu Guo , Wei Li , Hai-Xiao Wang , Jian-Hua Jiang

We introduce two-dimensional borane, a single-layered material of BH stoichiometry, with promising electronic properties. We show that, according to Density Functional Theory calculations, two-dimensional borane is semimetallic, with two…

Materials Science · Physics 2017-12-01 Miguel Martinez-Canales , Timur R. Galeev , Alexander I. Boldyrev , Chris J. Pickard

States of matter with nontrivial topology have been classified by their bulk symmetry properties. However, by cutting the topological insulator into ribbons, the symmetry of the system is reduced. By constructing effective Hamiltonians…

Mesoscale and Nanoscale Physics · Physics 2016-04-13 Augusto L. Araújo , Ernesto O. Wrasse , Gerson J. Ferreira , Tome M. Schmidt

The advance of topological photonics has heralded a revolution for manipulating light as well as for the development of novel photonic devices such as topological insulator lasers. Here, we demonstrate topological lasing of circular…

The design of a magnetic field source that can switch from a high field to a low field configuration by rotation by $90^\circ$ of a set of iron pieces is investigated using topology optimization. A Halbach cylinder is considered as the…

Instrumentation and Detectors · Physics 2019-01-11 R. Bjørk , A. R. Insinga

The magnitude of electron spin polarization in topologically protected surface states is an important parameter with respect to spintronics applications. In order to analyze the warped spin texture in Bi$_2$Te$_3$ thin films, we combine…

Mesoscale and Nanoscale Physics · Physics 2012-10-09 A. Herdt , L. Plucinski , G. Bihlmayer , G. Mussler , S. Döring , J. Krumrain , D. Grützmacher , S. Blügel , C. M. Schneider

Photonic pseudospin-1/2 systems, which exhibit Dirac cone dispersion at Brillouin zone corners in analogy to graphene, have been extensively studied in recent years. However, it is known that a linear band crossing of two bands cannot…

Optics · Physics 2020-10-07 Neng Wang , Ruo-Yang Zhang , C. T. Chan , Guo Ping Wang

We derive in the present work topological photonic states purely based on silicon, a conventional dielectric material, by deforming a honeycomb lattice of silicon cylinders into a triangular lattice of cylinder hexagons. The photonic…

Materials Science · Physics 2015-06-05 Long-Hua Wu , Xiao Hu

We present an inverse design approach to significantly improve the figures-of-merit for chiral photon elements and quantum emitters in topological photonic crystal slab waveguides. Beginning with a topological waveguide mode with a group…

Optics · Physics 2022-10-06 Eric Nussbaum , Nir Rotenberg , Stephen Hughes

This paper implements topology optimization on two-dimensional manifolds. In this paper, the material interpolation is implemented on a material parameter in the partial differential equation used to describe a physical field, when this…

Computational Physics · Physics 2020-04-22 Yongbo Deng , Zhenyu Liu , Jan G. Korvink