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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Cavity Quantum Electrodynamics with Second‐Order Topological Corner State
Xin Xie,Weixuan Zhang,Xiaowu He,Shiyao Wu,Jianchen Dang,Kai Peng,Feilong Song,Longlong Yang,Haiqiao Ni,Zhichuan Niu,Can Wang,Kuijuan Jin,Xiangdong Zhang,Xiulai Xu +13 more
TL;DR: In this article, a topological photonic crystal cavity is designed and fabricated into GaAs slabs with quantum dots embedded, and the enhancement of photoluminescence intensity and emission rate are both observed when the quantum dot is on resonance with the corner state.
Journal ArticleDOI
Parity-Time Symmetry in Non-Hermitian Complex Optical Media
TL;DR: It can be anticipated that this trendy field of interest will be indispensable in providing new perspectives in maneuvering the flow of light in the diverse physical platforms in optics, photonics, condensed matter, optoelectronics, and beyond, and will offer distinctive application prospects in novel functional materials.
Journal ArticleDOI
Experimental Realization of Type-II Weyl Points and Fermi Arcs in Phononic Crystal.
Boyang Xie,Hui Liu,Hua Cheng,Hua Cheng,Zhengyou Liu,Shuqi Chen,Shuqi Chen,Jianguo Tian,Jianguo Tian +8 more
TL;DR: The topological transitions observed at the WP frequencies and the topological surface acoustic waves between the Weyl frequencies are demonstrated, which are in good accordance with the theoretical analyses.
Journal ArticleDOI
Floquet topological phases of non-Hermitian systems
Hong Wu,Jun-Hong An +1 more
TL;DR: In this article, the authors proposed a scheme to retrieve the bulk boundary correspondence (BBC) and establish a complete description of the topological phases of the periodically driven non-Hermitian system both with and without the translation invariance.
Journal ArticleDOI
Photonic quantum Hall effect and multiplexed light sources of large orbital angular momenta
Babak Bahari,Liyi Hsu,Liyi Hsu,Si Hui Pan,Daryl Preece,Abdoulaye Ndao,Abdelkrim El Amili,Yeshaiahu Fainman,Boubacar Kante +8 more
TL;DR: In this article, a topological photonic crystal design was proposed to generate coherent orbital angular momenta beams of high quantum numbers from light travelling in leaky circular orbits at the interface between two topologically dissimilar photonic structures.
References
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