In the last decade, symmetry-protected bound states in continuum (BICs) have proven to be an important design principle for creating and enhancing devices reliant upon with high quality (Q) factors, such as sensors, lasers, those harmonic generation. However, we show, current implementations of BICs photonic crystal slabs can only found at center Brillouin zone below Bragg-diffraction limit, which fundamentally restricts their use single-frequency applications. By 3D-micro printing a...

Weyl points are robust point degeneracies in the band structure of a periodic material, which act as monopoles Berry curvature. They have been at forefront research three-dimensional topological materials (whether photonic, electronic or otherwise) they associated with novel behavior both bulk and on surface. Here, we present experimental observation charge-2 photonic low-index-contrast crystal fabricated by two-photon polymerization. The reflection spectrum obtained via Fourier Transform...

Abstract The discovery of artificial gauge fields controlling the dynamics uncharged particles that otherwise elude influence standard electromagnetic has revolutionised field quantum simulation. Hence, developing new techniques to induce these is essential boost simulation photonic structures. Here, we experimentally demonstrate generation an in a lattice by modifying topological charge light beam, overcoming need modify geometry along evolution or impose external fields. In particular,...

Edge modes in topological insulators are known to be robust against defects. We investigate if this also holds true when the defect is not static, but varies time. study influence of defects with time-dependent coupling on robustness transport along edge a Floquet system helically curved waveguides. Waveguide arrays fabricated via direct laser writing negative tone photoresist. find that single dynamic do destroy chiral current, even temporal modulation strong. Quantitative numerical...

The bulk-edge correspondence guarantees that the interface between two topologically distinct insulators supports at least one topological edge state is robust against static perturbations. Here, we address question of how dynamic perturbations affect robustness states. We illuminate limits protection for Floquet systems in special case a bulk. use independent quantum simulators based on coupled plasmonic and dielectric photonic waveguides to implement Su-Schriefer-Heeger model with...

Weyl points are point degeneracies that occur in momentum space of periodic materials, and associated with a quantized topological charge. We experimentally observe 3D micro-printed photonic crystal charge-2 can be split into two charge-1 as the protecting symmetry original is broken. Moreover, we use theoretical analysis to confirm where move within Brillouin zone strength breaking increases, it experiments using Fourier-transform infrared spectrometry. This micro-scale observation control...

Abstract Discrete spatial solitons are self-consistent solutions of the discrete nonlinear Schrödinger equation that maintain their shape during propagation. Here we show, using a pump-probe technique, soliton formation can be used to optically induce and control linear topological end state in bulk Su–Schrieffer–Heeger lattice, evanescently-coupled waveguide arrays. Specifically, observe an abrupt nonlinearly-induced transition above certain power threshold due inversion symmetry-breaking...

Topological materials have been at the forefront of research across various fields physics in hopes harnessing properties such as scatter-free transport due to protection from defects and disorder. Photonic systems are ideal test beds for topological models seek profit idea robustness applications. Recent progress 3D-printing microscopic structures has allowed a range implementations systems. We review recent work on realized particularly photonic crystals waveguide arrays fabricated by 3D...

Artificial gauge fields enable extending the control over dynamics of uncharged particles, by engineering potential landscape such that particles behave as if effective external are acting on them. Recent years have witnessed a growing interest in artificial generated either geometry or time-dependent modulation, they been enablers for topological phenomena and synthetic dimensions many physical settings, e.g., photonics, cold atoms acoustic waves. Here, we formulate experimentally...

Waves propagating in certain one-dimensional quasiperiodic lattices are known to exhibit a sharp localization transition. We theoretically predict and experimentally observe that the of light photonic quasicrystals is followed by second delocalization transition for some states on increasing modulation strength---an example reentrant further propose this phenomenon can be qualitatively captured dimerized tight-binding model with long-range couplings. This work furthers our understanding...

We present a quantum inspired image augmentation protocol which is applicable to classical images and, in principle, due its known formulation systems and machine learning the future. The technique relies on phenomenon Anderson localization. As we will illustrate by numerical examples changes wave properties interference effects resulting from scatterings at impurities material. explain that can be understood as multiplicative noise, counter-intuitively averages out, sampling over disorder...

We experimentally demonstrate that the next-nearest-neighbor-coupling (NNN-coupling) in an array of waveguides can naturally be negative. To do so, dielectric zig-zag shaped waveguide arrays are fabricated with direct laser writing (DLW). By changing angle shape it is possible to tune between positive and negative ratios nearest next-nearest-neighbor coupling, which also allows reduce impact NNN-coupling zero at correct respective angle. confirm existence NNN-couplings show improved accuracy...

Solitons are self-consistent solutions of the nonlinear Schr\"odinger equation that maintain their shape during propagation. Here we show, using a pump-probe technique, soliton formation can be used to optically induce and control linear topological end state in bulk Su-Schrieffer-Heeger lattice, evanescently-coupled waveguide arrays. Specifically, observe an abrupt nonlinearly-induced transition above certain power threshold due inversion symmetry-breaking bifurcation. Our results...

We show that edge states can be depopulated despite their topological protection. Local time-periodic driving results in hybridization of and bulk for certain frequencies. Experiments are performed using plasmonic dielectric waveguides.

Weyl Points points are topological degeneracies in the band structure of periodic media that robust against perturbations due to their integer charge. In article number 2100452, Christina Jörg and co-workers experimentally demonstrate splitting a quadratic point charge-2 into two linear with charge-1 3D micro-printed photonic crystals measure angle-resolved spectrum near-infrared via Fourier-transform infrared spectroscopy.

We experimentally demonstrate a negative NNN-coupling constant, arising naturally in dielectric waveguide structure, fabricated by direct-laser-writing, and show how we can tune between positive ratios for NN NNN coupling.

We present a quantum inspired image augmentation protocol which is applicable to classical images and, in principle, due its known formulation systems and machine learning the future. The technique relies on phenomenon Anderson localization. As we will illustrate by numerical examples changes wave properties interference effects resulting from scatterings at impurities material. explain that can be understood as multiplicative noise, counter-intuitively averages out, sampling over disorder...

We explore topological physics and boundary states of Chern Weyl systems experimentally using one-dimensional photonic multilayer structures endowed with additional artificial dimensions.

We theoretically predict and experimentally observe that the localization of light in one-dimensional photonic quasicrystals is followed by a second delocalization transition on increasing quasiperiodic modulation strength - an example reentrant transition.

We demonstrate all-optical active control of topological states in evanescently-coupled waveguide arrays. Soliton formation optically induces a linear end state the bulk Su-Schrieffer-Heeger lattice that we observe via pump-probe technique.

We theoretically predict and experimentally observe that nonlinearity can act to fractionally quantize the motion of solitons in photonic Thouless pumps. Such fractionalization is unique nonlinear regime.