Topological insulators (TIs) have unique highly conducting symmetry-protected surface states while the bulk is insulating, making them attractive for various applications in condensed matter physics. Recently, topological insulator materials have been tentatively applied for both near- and far-field wavefront manipulation of electromagnetic waves, yielding superior plasmonic properties in the

5 Feb 2018 Now, the researchers have found a way to use the properties of photonic topological insulators to build a new type of laser which shows a unique

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. The topological properties give rise to single mode lasing, The result suggests that topological insulators are potentially attractive as broadband pulsed modulators for the generation of short and ultrashort pulses in bulk solid‐state lasers, in addition to other promising applications in physics and computing. 2020-02-12 · Previous demonstrations of topological lasers have required an external laser source for optical pumping and have operated in the conventional optical frequency regime 5, 6, 7, 8. Here we Topological insulator lasers combine the concepts of topological insulators with the fundamentals of lasers, which introduce gain, loss, and demonstrate lasing action inatopologicalplatform.Specifically,inthepresenceofan artificial gauge field [38], an optical lattice consisting of resonators exhibits topological edge states. Incorporating We introduce a class of topological lasers based on the photonic Floquet topological insulator concept. Our result indicates that like the atomic layer graphene, the topological insulator Bi2Se3 could also operate as an effective saturable absorber for the passive mode locking of lasers at the telecommunication band. Upload an image to customize your repository’s social media preview.

Topological insulator laser

The residual un-uniformity of illumination results in … The formation of various multi-soliton patterns and noise-like pulse in a fiber laser passively mode-locked by a topological insulator based saturable absorber. Laser … Q‐switched and mode‐locked fibre lasers have been successfully demonstrated in ytterbium‐doped fibre laser cavity by taking an advantage of the optical absorption of antimony telluride (Sb 2 Te 3) material.The Sb 2 Te 3 was embedded into polyvinyl alcohol to function as a saturable absorber (SA). A Q‐switching pulses train was obtained by incorporating the SA into the laser … 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 2021-2-2 · A new hands-off probe uses light to explore the subtleties of electron behavior in a topological insulator . Laser light is usually linearly polarized, meaning that its waves oscillate in only one direction – up and down, in the example at left. But it can also be circularly polarized, at right, so its waves spiral like a corkscrew around Guo B. et al. Topological insulator: Bi 2 Se 3 /polyvinyl alcohol film-assisted multi-wavelength ultrafast erbium-doped fiber laser.

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 …

Figure 1: A 25 Mar 2015 From: IET Colloquium on Millimetre-wave and Terahertz Engineering & Technology 2015, 25 March 2015, Leeds. topological lasers have required an external laser source for optical pumping, and operated Topological insulator laser: Experiments. Science 359, eaar4005 . Spin injection and helicity control of surface spin photocurrent in a three dimensional topological insulator En tredimensionell (3D) topologisk isolator (TI) är en non-Hermitian Chern insulator.

Highly tunable magnetic coupling in ultrathin topological insulator films due to impurity resonances2020In: Physical Review B, ISSN 2469-9950, E-ISSN

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. 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.

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. Based on these features, we propose that a topological insulator quantum dot array can be operated as an electrically pumped continuous-wave THz laser. The proposed device can operate at room temperature, with power exceeding 10 mW and quantum efficiency reaching ∼50%.
Johanna tell

Segev.

N Von Den Driesch, MBE growth optimization of topological insulator Bi2Te3 films.
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superconductivity, heavy electron systems and topological insulators. group is also active users of synchrotron light sources and free electron lasers.

(b) Simplified sketch of the integer quantum Hall effect, which was the first topological insulator. (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. Applying topological physics to lasing creates more highly efficient and robust lasers.

2020-7-21

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.

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.