343 citations · 1.4k across the 38 of their papers we have counts for
21 papers · 1 filter
Time-resolved topology of aperiodically driven systems
Justin T. Cole, Christina Jörg, Terry A. Loring +1
Topological phases of periodically driven systems are commonly classified through Floquet Hamiltonians, whose definition relies on a repeated driving cycle. However, this framework…
Probing Local Topology in a Disordered Higher-Order Topological Insulator
Johannes Düreth, Simon Widmann, Philipp Gagel +13
Higher-order topology is prized for its ability to realize lower-dimensional boundary states which are stable beyond fine-tuning. However, disorder presents a failure mechanism tha…
Dynamically reconfigurable topological routing in nonlinear photonic systems
Stephan Wong, Simon Betzold, Sven Hofling +1
The propagation path of topologically protected states is bound to the interface between regions with different topology, and as such, the functionality of linear photonic devices…
Bi-stability and period-doubling cascade of frequency combs in exceptional-point lasers
Xingwei Gao, Hao He, Weng W. Chow +2
Recent studies have demonstrated that a laser can self-generate frequency combs when tuned near an exceptional point (EP), where two cavity modes coalesce. These EP combs induce pe…
Topological photonic crystal fibre
Bofeng Zhu, Kevin Hean, Stephan Wong +8
Photonic crystal fibres (PCFs) are optical fibres that guide light using a modulated dielectric medium. They provide an exceptionally versatile platform for various applications, t…
Quasinormal coupled-mode analysis of dynamic gain in exceptional-point lasers
Hao He, Xingwei Gao, Alexander Cerjan +1
One of the key features of lasers operating near exceptional points (EPs) is that the gain medium can support an oscillating population inversion above a pump threshold, leading to…
Tutorial: Classifying Photonic Topology Using the Spectral Localizer and Numerical -Theory
Alexander Cerjan, Terry A. Loring
Recently, the spectral localizer framework has emerged as an efficient approach to classifying topology in photonic systems featuring local nonlinearities and radiative environment…
Quantitative measure of topological protection in Floquet systems through the spectral localizer
Stephan Wong, Alexander Cerjan, Justin T. Cole
The standard understanding of topological protection from band theory is that a system's topology cannot change without first closing the bulk band gap. However, in Floquet systems…
Classifying topology in photonic crystal slabs with radiative environments
Stephan Wong, Terry A. Loring, Alexander Cerjan
In the recent years, photonic Chern materials have attracted substantial interest as they feature topological edge states that are robust against disorder, promising to realize def…
Dynamic gain and frequency comb formation in exceptional-point lasers
Xingwei Gao, Hao He, Scott Sobolewski +2
Exceptional points (EPs) -- singularities in the parameter space of non-Hermitian systems where two nearby eigenmodes coalesce -- feature unique properties with applications such a…
Local markers for crystalline topology
Alexander Cerjan, Terry A. Loring, Hermann Schulz-Baldes
Over the last few years, crystalline topology has been used in photonic crystals to realize edge- and corner-localized states that enhance light-matter interactions for potential d…
Classifying topology in photonic heterostructures with gapless environments
Kahlil Y. Dixon, Terry A. Loring, Alexander Cerjan
Photonic topological insulators exhibit bulk-boundary correspondence, which requires that boundary-localized states appear at the interface formed between topologically distinct in…
An operator-based approach to topological photonics
Alexander Cerjan, Terry A. Loring
Recently, the study of topological structures in photonics has garnered significant interest, as these systems can realize robust, non-reciprocal chiral edge states and cavity-like…
Observation of Quadratic (Charge-2) Weyl Point Splitting in Near-Infrared Photonic Crystals
Christina Jörg, Sachin Vaidya, Jiho Noh +4
Weyl points are point degeneracies that occur in momentum space of periodic materials, and are associated with a quantized topological charge. We experimentally observe in a 3D mic…
Observation of bound states in the continuum embedded in symmetry bandgaps
Alexander Cerjan, Christina Jörg, Sachin Vaidya +5
In the last decade, symmetry-protected bound states in the continuum (BICs) have proven to be an important design principle for creating and enhancing devices reliant upon states w…
Point-Defect-Localized Bound States in the Continuum in Photonic Crystals and Structured Fibers
Sachin Vaidya, Wladimir A. Benalcazar, Alexander Cerjan +1
We show that point defects in two-dimensional photonic crystals can support bound states in the continuum (BICs). The mechanism of confinement is a symmetry mismatch between the de…
Is single-mode lasing possible in an infinite periodic system?
Mohammed Benzaouia, Alexander Cerjan, Steven G. Johnson
In this Letter, we present a rigorous method to study the stability of periodic lasing systems. In a linear model, the presence of a continuum of modes (with arbitrarily close lasi…
Observation of a higher-order topological bound state in the continuum
Alexander Cerjan, Marius Jürgensen, Wladimir A. Benalcazar +2
Higher-order topological insulators are a recently discovered class of materials that can possess zero-dimensional localized states regardless of the dimension of the lattice. Here…
Observation of a charge-2 photonic Weyl point in the infrared
Sachin Vaidya, Jiho Noh, Alexander Cerjan +1
Weyl points are robust point degeneracies in the band structure of a periodic material, which act as monopoles of Berry curvature. They have been at the forefront of research in th…
Bound states in the continuum through environmental design
Alexander Cerjan, Chia Wei Hsu, Mikael C. Rechtsman
We propose a new paradigm for realizing bound states in the continuum (BICs) by engineering the environment of a system to control the number of available radiation channels. Using…
Experimental realization of a Weyl exceptional ring
Alexander Cerjan, Sheng Huang, Kevin P. Chen +2
Weyl points are isolated degeneracies in reciprocal space that are monopoles of the Berry curvature. This topological charge makes them inherently robust to Hermitian perturbations…