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
Reads0
Chats0
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
More filters
Journal ArticleDOI
Synthetic gauge potential and effective magnetic field in a Raman medium undergoing molecular modulation
TL;DR: In this paper, the authors theoretically demonstrate non-trivial topological effects for a probe field in a Raman medium undergoing molecular modulation processes, where the probe field exhibits topologically protected one-way edge state in the synthetic space, as well as Landau levels which manifests as suppression of both diffraction and sideband generation.
Journal ArticleDOI
Topological dislocation modes in three-dimensional acoustic topological insulators
TL;DR: In this article , a three-dimensional acoustic weak topological insulator with precisely controllable dislocations was used to measure the dispersion of the one-dimensional topological dislocation modes.
Journal ArticleDOI
Edge States in Dynamical Superlattices
Yiqi Zhang,Yiqi Zhang,Yaroslav V. Kartashov,Yaroslav V. Kartashov,Yaroslav V. Kartashov,Feng Li,Zhaoyang Zhang,Zhaoyang Zhang,Yanpeng Zhang,Milivoj R. Belić,Min Xiao,Min Xiao +11 more
TL;DR: In this paper, edge states and rich localization regimes available in one-dimensional dynamically modulated superlattices, both theoretically and numerically, are discussed. But the authors do not consider the effect of truncation on the quasi-energy band of the lattice.
Journal ArticleDOI
Interlayer Topological Transport and Devices based on Layer Pseudospins in Photonic Valley-Hall Phases
Xiaoxiao Wu,Zhenyu Li,Jian Chen,Xin Li,Jingxuan Tian,Yingzhou Huang,Shuxia Wang,Weixin Lu,Weixin Lu,Bo Hou,Bo Hou,Che Ting Chan,Weijia Wen,Weijia Wen +13 more
TL;DR: In this paper, the authors show that layer pseudospins exist in photonic valley-Hall phases, using vertically coupled designer surface plasmon crystals, a non-radiative system in open environment supporting tightly-confined propagating modes.
References
More filters
Journal ArticleDOI
Two-dimensional gas of massless Dirac fermions in graphene
Kostya S. Novoselov,A. K. Geim,Sergey V. Morozov,Da Jiang,Mikhail I. Katsnelson,Irina V. Grigorieva,S. V. Dubonos,A. A. Firsov +7 more
TL;DR: This study reports an experimental study of a condensed-matter system (graphene, a single atomic layer of carbon) in which electron transport is essentially governed by Dirac's (relativistic) equation and reveals a variety of unusual phenomena that are characteristic of two-dimensional Dirac fermions.
Journal ArticleDOI
Colloquium: Topological insulators
M. Z. Hasan,Charles L. Kane +1 more
TL;DR: In this paper, the theoretical foundation for topological insulators and superconductors is reviewed and recent experiments are described in which the signatures of topologically insulators have been observed.
Journal ArticleDOI
Quantum spin Hall effect in graphene
Charles L. Kane,Eugene J. Mele +1 more
TL;DR: Graphene is converted from an ideal two-dimensional semimetallic state to a quantum spin Hall insulator and the spin and charge conductances in these edge states are calculated and the effects of temperature, chemical potential, Rashba coupling, disorder, and symmetry breaking fields are discussed.
Journal ArticleDOI
New Method for High-Accuracy Determination of the Fine-Structure Constant Based on Quantized Hall Resistance
TL;DR: In this article, the Hall voltage of a two-dimensional electron gas, realized with a silicon metal-oxide-semiconductor field effect transistor, was measured and it was shown that the Hall resistance at particular, experimentally well-defined surface carrier concentrations has fixed values which depend only on the fine-structure constant and speed of light, and is insensitive to the geometry of the device.
Journal ArticleDOI
Quantized Hall conductance in a two-dimensional periodic potential
TL;DR: In this article, the Hall conductance of a two-dimensional electron gas has been studied in a uniform magnetic field and a periodic substrate potential, where the Kubo formula is written in a form that makes apparent the quantization when the Fermi energy lies in a gap.