Photonic Floquet topological insulators
Mikael C. Rechtsman,Julia M. Zeuner,Yonatan Plotnik,Yaakov Lumer,Daniel K. Podolsky,Felix Dreisow,Stefan Nolte,Mordechai Segev,Alexander Szameit +8 more
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TLDR
This work proposes and experimentally demonstrate a photonic topological insulator free of external fields and with scatter-free edge transport—a photonic lattice exhibiting topologically protected transport of visible light on the lattice edges.Abstract:
Topological insulators are a new phase of matter, with the striking property that conduction of electrons occurs only on their surfaces. In two dimensions, electrons on the surface of a topological insulator are not scattered despite defects and disorder, providing robustness akin to that of superconductors. Topological insulators are predicted to have wide-ranging applications in fault-tolerant quantum computing and spintronics. Substantial effort has been directed towards realizing topological insulators for electromagnetic waves. One-dimensional systems with topological edge states have been demonstrated, but these states are zero-dimensional and therefore exhibit no transport properties. Topological protection of microwaves has been observed using a mechanism similar to the quantum Hall effect, by placing a gyromagnetic photonic crystal in an external magnetic field. But because magnetic effects are very weak at optical frequencies, realizing photonic topological insulators with scatter-free edge states requires a fundamentally different mechanism-one that is free of magnetic fields. A number of proposals for photonic topological transport have been put forward recently. One suggested temporal modulation of a photonic crystal, thus breaking time-reversal symmetry and inducing one-way edge states. This is in the spirit of the proposed Floquet topological insulators, in which temporal variations in solid-state systems induce topological edge states. Here we propose and experimentally demonstrate a photonic topological insulator free of external fields and with scatter-free edge transport-a photonic lattice exhibiting topologically protected transport of visible light on the lattice edges. Our system is composed of an array of evanescently coupled helical waveguides arranged in a graphene-like honeycomb lattice. Paraxial diffraction of light is described by a Schrodinger equation where the propagation coordinate (z) acts as 'time'. Thus the helicity of the waveguides breaks z-reversal symmetry as proposed for Floquet topological insulators. This structure results in one-way edge states that are topologically protected from scattering.read more
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Photonic Hall effect and helical Zitterbewegung in a synthetic Weyl system
Weimin Ye,Yachao Liu,Yachao Liu,Jianlong Liu,Simon A. R. Horsley,Shuangchun Wen,Shuang Zhang +6 more
TL;DR: Synthetic Weyl points are constructed in a photonic crystal that consists of a honeycomb array of coupled rods with slowly varying radii along the direction of propagation that could serve as a system to study the phenomenon known as Berry phase effect in the transmission of light.
Posted Content
Topological protection of perturbed edge states.
TL;DR: In this article, a quantitative description of the low energy edge states at the interface between two-dimensional topological insulators is proposed, which are modeled by continuous Hamiltonians as systems of Dirac equations that are amenable to a large class of random perturbations.
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Topological insulator properties of photonic kagome helical waveguide arrays
Hua Zhong,Rong Wang,Fangwei Ye,Jingwen Zhang,Lei Zhang,Yanpeng Zhang,Milivoj R. Belic,Yiqi Zhang +7 more
TL;DR: In this paper, the topological insulator properties of the kagome helical waveguide array were investigated by utilizing theoretical and numerical means, and the Berry curvature and Chern number of the band structure were calculated.
Journal ArticleDOI
Localized gap modes in nonlinear dimerized Lieb lattices
TL;DR: In this paper, the conditions under which diffractionless gap modes can be formed and propagated also in the presence of a cubic on-site (Kerr) nonlinearity were investigated.
Journal ArticleDOI
Theory of chiral edge state lasing in a two-dimensional topological system
Abstract: This paper presents a theoretical study of the distinctive properties of topological lasers focusing on the effects that emerge from the chiral nature of the lasing modes already at the semiclassical level of nonlinear laser dynamics.
References
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