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A Short Course on Topological Insulators : Band Structure and

Topological insulator laser using valley-hall photonic crystals Gong, Yongkang , Wong, Stephan , Bennett, Anthony J. , Huffaker, Diana L. and Oh, Sang Soon 2020. Topological insulator laser using valley-hall photonic crystals. Ghimire and co-workers embarked on experimental studies of topological insulators by investigating under what conditions the materials would generate higher harmonics of incoming laser light. This comes after having carried out such experiments on conventional insulators and semiconductors for about a decade. Topological insulators are a phase of matter with an insulating bulk and conducting edges. A topological insulator is characterized by a bulk bandgap where topological gapless unidirectional edge states reside. These edge states are robust to any perturbation that does not close the bandgap.

Topological insulator laser

A topological insulator is an extraordinary material - it acts as an electrical bulk insulator that allows an electrical current flow along its surface. The surface current is topologically protected from a defect or scatterer. 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.

Near-Field-Mediated Photon-Electron Interactions - Nahid

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.

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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.

Bismuth in its pure state, is a semimetal with a small electronic band gap. 2018-11-22 · Recently, topological microcavity lasers designed based on the bulk-edge correspondence have been demonstrated 4, 5, 6, 21, 22. While the topological microcavities exhibited single-mode lasing, the We propose a system that exploits the fundamental features of topological photonics and synthetic dimensions to force many semiconductor laser resonators to synchronize, mutually lock, and under suitable modulation emit a train of transform-limited mode-locked pulses. 2019-10-29 · Floquet topological insulator laser Sergey K. Ivanov, Yiqi Zhang, Yaroslav V. Kartashov, Dmitry V. Skryabin (Submitted on 29 Oct 2019) We introduce a class of topological lasers based on the photonic Floquet topological insulator concept. 2021-04-12 · Topological insulators have notable manifestations of electronic properties. The helicity-dependent photocurrents in such devices are underpinned by spin momentum-locking of surface Dirac Here, we demonstrate a nonmagnetic topological insulator laser system exhibiting topologically protected transport in the cavity.
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Topology of non-Hermitian systems unraveled. The study of topological materials has been an important task in condensed matter the gap of laser sources at the sub-millimeter wavelengths [2017-11-24] · First Här kombinerar vi polarisering-variabel 7-eV laser med spinn - och H., Liu, C. -X., Zhang, S. -C. Spin-orbital texture in topological insulators. Direct bandgap group IV epitaxy on Si for laser applications. N Von Den Driesch, MBE growth optimization of topological insulator Bi2Te3 films.

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.
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Conical Intersections in Physics - Jonas Larson, Erik Sjoqvist

(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.