Fractal-like photonic lattices and localized states arising from singular and nonsingular flatbands

AbstractFlat-band systems have attracted considerable interest in different branches of physics in the past decades, providing a flexible platform for studying fundamental phenomena associated with completely dispersionless bands within the whole Brillouin zone. Engineered flat-band structures have now been realized in a variety of systems, in particular, in the field of photonics. Flat-band localization, as an important phenomenon in solid-state physics, is fundamentally interesting in the exploration of exotic ground-state properties of many-body systems. However, direct observation of some flat-band phenomena is highly nontrivial in conventional condensed-matter systems because of intrinsic limitations. In this article, we briefly review recent developments on flat-band localization and the associated phenomena in various photonic lattices, including compact localized states, unconventional line states, and noncontractible loop states. We show that the photonic lattices offer a convenient platform for probing the underlying physics of flat-band systems, which may provide inspiration for exploring the fundamentals and applications of flat-band physics in other structured media from metamaterials to nanophotonic materials.

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LOCALIZED STATES AND BAND STRUCTURE

Le Journal de Physique Colloques ◽

10.1051/jphyscol:1972304 ◽

1972 ◽

Vol 33 (C3) ◽

pp. C3-21-C3-25 ◽

Cited By ~ 3

Author(s):

F. BASSANI

Keyword(s):

Band Structure ◽

Localized States

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COMPARISON OF OPTICALLY INDUCED LOCALIZED STATES IN CHALCOGENIDE GLASSES AND THEIR CRYSTALLINE COUNTERPARTS

Le Journal de Physique Colloques ◽

10.1051/jphyscol:1981482 ◽

1981 ◽

Vol 42 (C4) ◽

pp. C4-383-C4-386 ◽

Cited By ~ 4

Author(s):

S. G. Bishop ◽

B. V. Shanabrook ◽

U. Strom ◽

P. C. Taylor

Keyword(s):

Chalcogenide Glasses ◽

Localized States ◽

Optically Induced

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Low-Temperature Operation of Green, Blue and UV InGaN/GaN Multiple-Quantum-Well Light-Emitting Diodes

MRS Proceedings ◽

10.1557/proc-764-c5.5 ◽

2003 ◽

Vol 764 ◽

Author(s):

X. A. Cao ◽

S. F. LeBoeuf ◽

J. L. Garrett ◽

A. Ebong ◽

L. B. Rowland ◽

...

Keyword(s):

Quantum Well ◽

Light Emitting Diodes ◽

Multiple Quantum Well ◽

Light Output ◽

Localized States ◽

Multiple Quantum ◽

Nonradiative Recombination ◽

Light Emitting ◽

Temperature Range ◽

Green Leds

Absract:Temperature-dependent electroluminescence (EL) of InGaN/GaN multiple-quantum-well light-emitting diodes (LEDs) with peak emission energies ranging from 2.3 eV (green) to 3.3 eV (UV) has been studied over a wide temperature range (5-300 K). As the temperature is decreased from 300 K to 150 K, the EL intensity increases in all devices due to reduced nonradiative recombination and improved carrier confinement. However, LED operation at lower temperatures (150-5 K) is a strong function of In ratio in the active layer. For the green LEDs, emission intensity increases monotonically in the whole temperature range, while for the blue and UV LEDs, a remarkable decrease of the light output was observed, accompanied by a large redshift of the peak energy. The discrepancy can be attributed to various amounts of localization states caused by In composition fluctuation in the QW active regions. Based on a rate equation analysis, we find that the densities of the localized states in the green LEDs are more than two orders of magnitude higher than that in the UV LED. The large number of localized states in the green LEDs are crucial to maintain high-efficiency carrier capture at low temperatures.

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Light Localization and Navigation in Optically-Induced Photonic Lattices

10.21236/ada498286 ◽

2009 ◽

Author(s):

Zhigang Chen

Keyword(s):

Photonic Lattices ◽

Light Localization ◽

Optically Induced

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Quantum transport in non-Markovian dynamically disordered photonic lattices

Physical Review A ◽

10.1103/physreva.103.033520 ◽

2021 ◽

Vol 103 (3) ◽

Cited By ~ 1

Author(s):

Ricardo Román-Ancheyta ◽

Barış Çakmak ◽

Roberto de J. León-Montiel ◽

Armando Perez-Leija

Keyword(s):

Quantum Transport ◽

Photonic Lattices

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Quenched topological boundary modes can persist in a trivial system

Communications Physics ◽

10.1038/s42005-021-00645-w ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Ching Hua Lee ◽

Justin C. W. Song

Keyword(s):

Probability Density ◽

Power Law ◽

Localized States ◽

Topological Phase ◽

Boundary Mode ◽

Temporal Boundary ◽

And Control ◽

Topological Boundary

AbstractTopological boundary modes can occur at the spatial interface between a topological and gapped trivial phase and exhibit a wavefunction that exponentially decays in the gap. Here we argue that this intuition fails for a temporal boundary between a prequench topological phase that possess topological boundary eigenstates and a postquench gapped trivial phase that does not possess any eigenstates in its gap. In particular, we find that characteristics of states (e.g., probability density) prepared in a topologically non-trivial system can persist long after it is quenched into a gapped trivial phase with spatial profiles that appear frozen over long times postquench. After this near-stationary window, topological boundary mode profiles decay albeit, slowly in a power-law fashion. This behavior highlights the unusual features of nonequilibrium protocols enabling quenches to extend and control localized states of both topological and non-topological origins.

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