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- Tiguntseva, Ekaterina, et al.
(författare)
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Room-Temperature Lasing from Mie-Resonant Nonplasmonic Nanoparticles
- 2020
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Ingår i: ACS Nano. - : American Chemical Society (ACS). - 1936-086X .- 1936-0851. ; 14:7, s. 8149-8156
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Tidskriftsartikel (refereegranskat)abstract
- Subwavelength particles supporting Mie resonances underpin a strategy in nanophotonics for efficient control and manipulation of light by employing both an electric and a magnetic optically induced multipolar resonant response. Here, we demonstrate that monolithic dielectric nanoparticles made of CsPbBr3 halide perovskites can exhibit both efficient Mie-resonant lasing and structural coloring in the visible and near-IR frequency ranges. We employ a simple chemical synthesis with nearly epitaxial quality for fabricating subwavelength cubes with high optical gain and demonstrate single-mode lasing governed by the Mie resonances from nanocubes as small as 310 nm by the side length. These active nanoantennas represent the most compact room-temperature nonplasmonic nanolasers demonstrated until now.
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2. |
- Bokai, Kirill A., et al.
(författare)
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Visualization of graphene grain boundaries through oxygen intercalation
- 2021
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Ingår i: Applied Surface Science. - : Elsevier BV. - 0169-4332. ; 565
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Tidskriftsartikel (refereegranskat)abstract
- Efficient control over the grain boundaries (GBs) is a vital aspect in optimizing the graphene growth conditions. A number of methods for visualization of GBs were developed for graphene grown on weakly interacting surfaces. Here, we utilize oxygen intercalation to reveal GBs and study their morphology for graphene strongly bound to the cobalt surface. We demonstrate that upon the intercalation of oxygen, GBs in polycrystalline graphene become easily detectable due to graphene cracking and selective oxidation of the substrate, thus giving a direct insight into the graphene micro- and nanostructure by means of different electron microscopy methods, including scanning electron microscopy, photoemission microscopy and low-energy electron microscopy.
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4. |
- Severo, J. H. F., et al.
(författare)
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Magnetic islands and plasma rotation in the Tokamak Chauffage Alfven Bresilien tokamak
- 2004
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Ingår i: Physics of Plasmas. - : AIP Publishing. - 1070-664X .- 1089-7674. ; 11:2, s. 846-848
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Tidskriftsartikel (refereegranskat)abstract
- Collisional plasma rotation in the Tokamak Chauffage Alfven Bresilien (TCABR) tokamak [J. H. F. Severo, I. C. Nascimento, V. S. Tsypin, and R. M. O. Galvao, Nucl. Fusion 43, 1047 (2003)] has been experimentally studied. It was found that the measured plasma poloidal rotation velocity agrees within error limits with neoclassical theoretical predictions, and toroidal velocity with experimental results obtained in analogous tokamaks, almost everywhere along the minor radius r, except for measurements at r/asimilar or equal to0.56 and r/asimilar or equal to0.89 (the minor radius of TCABR tokamak a=18 cm). For the first point, the measured plasma rotation velocities are higher than the velocity of the background plasma, respectively similar to30% and similar to10% for the poloidal and toroidal rotation velocities. Using a set of 22 Mirnov coils displaced poloidally, magnetic field perturbations were measured in shots adjusted to reproduce the ones of the previous plasma rotation measurements, and the results confirm that in the region r/asimilar or equal to0.89 the plasma rotates together with the magnetic island (3,1).
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