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We introduce a class of topological lasers based on the photonic Floquet topological insulator concept. The proposed system is realized as a truncated array of lasing helical waveguides, where the We introduce a class of topological lasers based on the photonic Floquet topological insulator concept. 2020-10-07 · (a) Topological insulator: a two-dimensional (2D) material that is insulating in the bulk but exhibits perfect conduction on the edge. (b) Simplified sketch of the integer quantum Hall effect, which was the first topological insulator.

These lasers exploit the Floquet topological edge states in a 1D array of ring resonators, which corresponds to a 2D Topological insulators (TIs), are novel two-dimension materials, which can act as effective saturable absorbers (SAs) in a fiber laser. Moreover, based on the evanescent wave interaction, deposition of the TI on microfiber would create an effective SA, which has combined advantages from the strong nonlinear optical response in TI material together with the sufficiently-long-range interaction Topological Trivial 1550 1552 1554 1556 1558 1560 Wavelength [nm] 0 0.2 0.4 0.6 0.8 1 Spectrum [au] Topological Trivial Topological Lasing Mode Topological Photonics Meets Lasers T opological insulators represent a new phase of matt er: insulating in bulk, but with a robust edge conductance. These topo-logical edge states are extremely robust, show A new hands-off probe uses light to explore electron behavior in a topological insulator Just as pressing a guitar string produces a higher pitch, sending laser light through a material can shift anomalous topological insulators,19,20 topologically protected path entanglements,34 unpaired Dirac cones,35 topological edge states in quasicrystals,21 solitons,36–38 topological Anderson insulator,22,39,40 topological phases in synthetic dimensions,24 guiding light by artifi-cial gauge fields,41 and others. Note that driven topological systems, This Conference Presentation, Towards electrically pumped topological insulator lasers was recorded at Photonics West 2020 held in San Francisco, California, United States. Conference Presentation This content is available for download via your institution's subscription. We show that for the topological insulator phase, the photoelectromagnetic effect amplitude is deﬁned by the number of incident radiation quanta, whereas for the trivial insulator phase, it depends on the power in a laser pulse irrespective of its wavelength. Topological insulator laser: rate-equation model.

Forskning vid Uppsala universitet - Uppsala universitet

Upload an image to customize your repository’s social media preview. Images should be at least 640×320px (1280×640px for best display). Abstract We reported on the generation of femtosecond pulse in a fiber ring laser by using a polyvinyl alcohol (PVA)-based topological insulator (TI), Bi 2 Se 3 saturable absorber (SA). The PVA-TI composite has a low saturable optical intensity of 12 MW/cm 2 and a modulation depth of ~3.9%.

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The topological properties of the system give rise to single mode lasing, robustness against fabrication defects, and higher slope efficiencies compared to its trivial counterpart. Topological insulators are electrically insulating in their bulk, but they can conduct electricity extremely well on their surfaces (or edges) via special electronic states that are protected from fluctuations in their environment. Within these states, electrons can only travel in one direction (or channel) and do not backscatter. Topological insulators were first realized in 2D in system containing HgTe quantum wells sandwiched between cadmium telluride in 2007. The first 3D topological insulator to be realized experimentally was Bi 1 − x Sb x.

(c) Simplified dispersion relation for Topological Insulators I. INTRODUCTION Topological quantum materials (TQMs) represent spe-cial classes of materials whose electronic structures can be characterized by topological invariants protected by certain symmetries, and the breaking of these symmetries can lead to intriguing topological phase transitions. Time- These are special materials that are insulators in their interior but conduct a “super-current” on their surface: the current on their surface is not affected by defects, sharp corners or disorder; it continues unidirectionally without being scattered. Top view photograph of the intensity lasing pattern of the topological insulator laser.
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effects in a unique way: the topological insulator laser.These are lasers whose lasing mode exhibits topologically protected transport wit hout magnetic fields.The underlying topological properties lead to a highly efficient laser, robust to defects and disorder,with single-mode lasing In the topological-insulator laser demonstrated by the Technion-CREOL team, laser light goes around the perimeter unobstructed by sharp corners or other local disorder, and eventually exits through the output port. [Image: S. Wittek (CREOL) and M.A. Bandres (Technion)] TOPOLOGICAL PHOTONICS Topological insulator laser: Experiments Miguel A. Bandres,1* Steffen Wittek, 2* Gal Harari,1* Midya Parto, Jinhan Ren,2 Mordechai Segev,1† Demetrios N. Christodoulides, 2† Mercedeh Khajavikhan † Physical systems exhibiting topological inva riants are naturally endowed with robustness On the technological side, the topological insulator laser provides a route to arrays of semiconductor lasers that operate as one single-mode high-power laser coupled efficiently into an output port. All Science Journal Classification (ASJC) codes Here we demonstrate a nonmagnetic topological insulator laser system exhibiting topologically protected transport in the cavity.

Posted: Feb 01, 2018: Future of semiconductor lasing: Topological insulator lasers (Nanowerk News) Israeli and US researchers have developed a new, highly efficient coherent and robust semiconductor laser system: the topological insulator laser.The findings are presented in two new joint research papers, one describing theory ("Topological insulator laser… 2017-2-1 · Q-switching fibre laser using Topological Insulator (TI) Bismuth Selenide (Bi 2 Se 3)..
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Andreas Lindblad - Assistant Professor - Uppsala University

On the technological side, the topological insulator laser provides a route to arrays of semiconductor lasers that operate as one single-mode high-power laser coupled efficiently into an output port. AB - Topological insulators are phases of matter characterized by topological edge States that propagate in a unidirectional manner that is robust to imperfections and disorder. Scientists and engineers have created the first electrically-driven 'topological' laser, which has the ability to route light particles around corners -- and to cope with defects in the Studies on three dimensional topological insulators (TIs) such as Bi 2 Te 3, Bi 2 Se 3, and Sb 2 Te 3 over the past decade have been intense due to their unique physical properties and potential applications for spintronics and quantum computing.

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Olle Eriksson - School of Science and Technology - Örebro

The Upload an image to customize your repository’s social media preview. Images should be at least 640×320px (1280×640px for best display). 2018-6-8 · The experiment nicely showed that in the topological insulator laser the synthetic magnetic field enables lasing in a chiral edge mode, outperforming the same laser array without the synthetic magnetic field (i.e., in a topological trivial phase) in terms of efficiency, coherence and robustness against disorder. Such a result seem rather promising toward the realization of miniaturized high power and stable laser … Topological insulator laser: rate-equation model.