Topological photonics

Reviews of Modern Physics, Journal Year: 2019, Volume and Issue: 91(1)

Published: March 25, 2019

The robustness of the integer quantum Hall effect electron systems is due to existence a topological invariant that characterizes variation wave function over Brillouin zone. Topological phenomena are generic features waves in periodic media, and this article reviews how photonic such as waveguide arrays metamaterials allow exploration application effects new physical regimes devices.

Language: Английский

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Acoustic higher-order topological insulator on a kagome lattice

Nature Materials, Journal Year: 2018, Volume and Issue: 18(2), P. 108 - 112

Published: Dec. 13, 2018

Language: Английский

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Topological phases in acoustic and mechanical systems

Nature Reviews Physics, Journal Year: 2019, Volume and Issue: 1(4), P. 281 - 294

Published: March 1, 2019

Language: Английский

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Topological Phases of Non-Hermitian Systems

Physical Review X, Journal Year: 2018, Volume and Issue: 8(3)

Published: Sept. 24, 2018

Recent experimental advances in controlling dissipation have brought about unprecedented flexibility engineering non-Hermitian Hamiltonians open classical and quantum systems. A particular interest centers on the topological properties of systems, which exhibit unique phases with no Hermitian counterparts. However, systematic understanding analogy periodic table insulators superconductors has been achieved. In this paper, we develop a coherent framework After elucidating physical meaning mathematical definition phases, start one-dimensional lattices, counterparts are found to be characterized by an integer winding number even symmetry constraint, reminiscent Hall insulator system nonzero number, is experimentally measurable from wave-packet dynamics, shown robust against disorder, phenomenon observed Hatano-Nelson model asymmetric hopping amplitudes. We also unveil novel bulk-edge correspondence that features infinite (quasi-)edge modes. then apply K-theory systematically classify all Altland-Zirnbauer classes dimensions. The obtained unifies time-reversal particle-hole symmetries, leading highly nontrivial predictions such as absence two provide concrete examples for AZ zero one particular, identify Z2 index arbitrary channels. Our work lays cornerstone unified role topology

Language: Английский

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Visualization of Higher-Order Topological Insulating Phases in Two-Dimensional Dielectric Photonic Crystals

Physical Review Letters, Journal Year: 2019, Volume and Issue: 122(23)

Published: June 14, 2019

The studies of topological phases matter have been developed from condensed physics to photonic systems, resulting in fascinating designs robust devices. Recently, higher-order insulators investigated as a novel phase beyond the conventional bulk-boundary correspondence. Previous mainly focused on multipole systems with negative coupling between lattice sites. Here we experimentally demonstrate that second-order insulating without can be realized two-dimensional dielectric crystals. We visualize both one-dimensional edge states and zero-dimensional corner by using near-field scanning technique. Our findings open new research frontiers for provide mechanism light manipulating hierarchical way.

Language: Английский

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Higher-order band topology

Nature Reviews Physics, Journal Year: 2021, Volume and Issue: 3(7), P. 520 - 532

Published: June 15, 2021

Language: Английский

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Topological hybrid silicon microlasers

Nature Communications, Journal Year: 2018, Volume and Issue: 9(1)

Published: March 1, 2018

Abstract Topological physics provides a robust framework for strategically controlling wave confinement and propagation dynamics. However, current implementations have been restricted to the limited design parameter space defined by passive topological structures. Active systems provide more general where different fundamental symmetry paradigms, such as those arising from non-Hermiticity nonlinear interaction, can generate new landscape its applications. Here, we bridge this gap present an experimental investigation of active photonic system, demonstrating hybrid silicon microlaser array respecting charge-conjugation symmetry. The created features favour lasing protected zero mode, single-mode laser action in desired state prevails even with intentionally introduced perturbations. demonstrated is implemented on silicon-on-insulator substrate, thereby readily suitable integrated photonics applications optical communication computing.

Language: Английский

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Visualization of a Unidirectional Electromagnetic Waveguide Using Topological Photonic Crystals Made of Dielectric Materials

Physical Review Letters, Journal Year: 2018, Volume and Issue: 120(21)

Published: May 22, 2018

We demonstrate experimentally that a photonic crystal made of ${\mathrm{Al}}_{2}{\mathrm{O}}_{3}$ cylinders exhibits topological time-reversal symmetric electromagnetic propagation, similar to the quantum spin Hall effect in electronic systems. A pseudospin degree freedom system representing different states orbital angular momentum arises due deformation from ideal honeycomb lattice. It serves as analogue Kramers pair. visualized qualitatively and measured quantitatively microwaves specific propagate only one direction along interface between trivial one. As conventional dielectric material is used local real-space manipulations are required, our scheme can be extended visible light inspire many future applications field photonics beyond.

Language: Английский

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Second-order topology and multidimensional topological transitions in sonic crystals

Nature Physics, Journal Year: 2019, Volume and Issue: 15(6), P. 582 - 588

Published: March 18, 2019

Language: Английский

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Tunable and Active Phononic Crystals and Metamaterials

Applied Mechanics Reviews, Journal Year: 2020, Volume and Issue: 72(4)

Published: Feb. 26, 2020

Abstract Phononic crystals (PCs) and metamaterials (MMs) can exhibit abnormal properties, even far beyond those found in nature, through artificial design of the topology or ordered structure unit cells. This emerging class materials has diverse application potentials many fields. Recently, concept tunable PCs MMs been proposed to manipulate a variety wave functions on demand. In this review, we survey recent developments active MMs, including bandgap engineering, anomalous behaviors propagation, as well manipulation waves based different regulation mechanisms: mechanical reconfiguration with multifield coupling. We conclude by outlining future directions field.

Language: Английский

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