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
Citations
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Topological edge states in acoustic Kagome lattices
TL;DR: In this paper, an acoustic Kagome lattice formed by an array of interconnected resonant cavities exhibits a new class of topological states protected by C3 symmetry, and it is characterised by a topological invariant in the form of a winding number in Pauli vector space.
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Observation of Topological Band Gap Solitons.
TL;DR: In this paper, a laser-written waveguide array with periodic variations along the waveguide axis was used to observe solitons in the bulk of a photonic Floquet topological insulator, where the nonlinearity arises from the optical Kerr effect of the ambient glass.
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Photonic Topological Insulator in Synthetic Dimensions
Eran Lustig,Steffen Weimann,Yonatan Plotnik,Yaakov Lumer,Miguel A. Bandres,Alexander Szameit,Mordechai Segev +6 more
TL;DR: In this paper, the first photonic topological insulator in synthetic dimensions was demonstrated, which is the first attempt to realize topological lattices with synthetic dimensions in photonics, where they are connected to physical phenomena in high dimensions, interacting photons, and more.
Journal ArticleDOI
Realistic Floquet Semimetal with Exotic Topological Linkages between Arbitrarily Many Nodal Loops.
TL;DR: This Letter presents a class of exotic Floquet topological phases that has hitherto not been proposed in any realistic setup and proposes to use both a Berry-phase related winding number and the Alexander polynomial topological invariant to characterize the fascinating linkages among the nodal loops.
Journal ArticleDOI
Lieb polariton topological insulators
Chunyan Li,Fangwei Ye,Xianfeng Chen,Yaroslav V. Kartashov,Yaroslav V. Kartashov,Yaroslav V. Kartashov,Albert Ferrando,Lluis Torner,Lluis Torner,Dmitry V. Skryabin,Dmitry V. Skryabin +10 more
TL;DR: In this article, the spin-orbit coupling, stemming from the transverse electric--transverse magnetic energy splitting, and the Zeeman effect in semiconductor microcavities supporting exciton-polariton quasiparticles, results in the appearance of unidirectional linear topological edge states.
References
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