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300 results on '"Choi, D-Y."'

1. Ultrafast all-optical second harmonic wavefront shaping

Author

Sinelnik, A., Lam, S. H., Coviello, F., Klimmer, S., Della Valle, G., Choi, D. -Y., Pertsch, T., Soavi, G., and Staude, I.

Subjects
Physics - Optics, Quantum Physics
Abstract

Optical communication can be revolutionized by encoding data into the orbital angular momentum of light beams. However, state-of-the-art approaches for dynamic control of complex optical wavefronts are mainly based on liquid crystal spatial light modulators or miniaturized mirrors, which suffer from intrinsically slow response times. Here, we experimentally realize a hybrid meta-optical system that enables complex control of the wavefront of light with pulse-duration limited dynamics. Specifically, by combining ultrafast polarization switching in a WSe2 monolayer with a dielectric metasurface, we demonstrate second harmonic beam deflection and structuring of orbital angular momentum on the femtosecond timescale. Our results pave the way to robust encoding of information for free space optical links, while reaching response times compatible with real-world telecom applications.

Published
2023

2. Compact Brillouin devices through hybrid integration on Silicon

Author

Morrison, B., Casas-Bedoya, A., Ren, G., Vu, K., Liu, Y., Zarifi, A., Nguyen, T. G., Choi, D-Y., Marpaung, D., Madden, S., Mitchell, A., and Eggleton, B. J.

Subjects
Physics - Optics
Abstract

A range of unique capabilities in optical and microwave signal processing have been demonstrated using stimulated Brillouin scattering. The desire to harness Brillouin scattering in mass manufacturable integrated circuits has led to a focus on silicon-based material platforms. Remarkable progress in silicon-based Brillouin waveguides has been made, but results have been hindered by nonlinear losses present at telecommunications wavelengths. Here, we report a new approach to surpass this issue through the integration of a high Brillouin gain material, As2S3, onto a silicon chip. We fabricated a compact spiral device, within a silicon circuit, achieving an order of magnitude improvement in Brillouin amplification. To establish the flexibility of this approach, we fabricated a ring resonator with free spectral range precisely matched to the Brillouin shift, enabling the first demonstration of Brillouin lasing in a silicon integrated circuit. Combining active photonic components with the SBS devices shown here will enable the creation of compact, mass manufacturable optical circuits with enhanced functionality.

Published
2017

3. Active Temporal Multiplexing of Indistinguishable Heralded Single Photons

Author

Xiong, C., Zhang, X., Liu, Z., Collins, M. J., Mahendra, A., Helt, L. G., Steel, M. J., Choi, D. -Y., Chae, C. J., Leong, P. H. W., and Eggleton, B. J.

Subjects
Quantum Physics
Abstract

It is a fundamental challenge in quantum optics to deterministically generate indistinguishable single photons through non-deterministic nonlinear optical processes, due to the intrinsic coupling of single- and multi-photon generation probabilities in these processes. Actively multiplexing photons generated in many temporal modes can decouple these probabilities, but key issues are to minimize resource requirements to allow scalability, and to ensure indistinguishability of the generated photons. We demonstrate the multiplexing of photons from four temporal modes solely using fiber-integrated optics and off-the-shelf electronic circuits. We show a 100% enhancement to the single photon output probability without introducing additional multi-photon noise. Photon indistinguishability is confirmed by a four-fold Hong-Ou-Mandel quantum interference with a 91% visibility. Our demonstration paves the way for scalable multiplexing of many non-deterministic photon sources to a single near-deterministic source, which will be of benefit to future quantum photonic technologies., Comment: 13 pages, 6 figures

Published
2015
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4. A compact and reconfigurable silicon nitride time-bin entanglement circuit

Author

Xiong, C., Zhang, X., Mahendra, A., He, J., Choi, D. -Y., Chae, C. J., Marpaung, D., Leinse, A., Heideman, R. G., Hoekman, M., Roeloffzen, C. G. H., Oldenbeuving, R. M., van Dijk, P. W. L., Taddei, C., Leong, P. H. W., and Eggleton, B. J.

Subjects
Quantum Physics
Abstract

Photonic chip based time-bin entanglement has attracted significant attention because of its potential for quantum communication and computation. Useful time-bin entanglement systems must be able to generate, manipulate and analyze entangled photons on a photonic chip for stable, scalable and reconfigurable operation. Here we report the first time-bin entanglement photonic chip that integrates time-bin generation, wavelength demultiplexing and entanglement analysis. A two-photon interference fringe with an 88.4% visibility is measured (without subtracting any noise), indicating the high performance of the chip. Our approach, based on a silicon nitride photonic circuit, which combines the low-loss characteristic of silica and tight integration features of silicon, paves the way for scalable real-world quantum information processors., Comment: 4 pages, 5 figures

Published
2015
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5. Generation of correlated photon pairs in a chalcogenide As2S3 waveguide

Author

Xiong, C., Marshall, G. D., Peruzzo, A., Lobino, M., Clark, A. S., Choi, D. -Y., Madden, S. J., Natarajan, C. M., Tanner, M. G., Hadfield, R. H., Dorenbos, S. N., Zijlstra, T., Zwiller, V., Thompson, M. G., Rarity, J. G., Steel, M. J., Luther-Davies, B., Eggleton, B. J., and O'Brien, J. L.

Subjects
Quantum Physics, Physics - Optics
Abstract

We demonstrate the first 1550 nm correlated photon-pair source in an integrated glass platform-a chalcogenide As2S3 waveguide. A measured pair coincidence rate of 80 per second was achieved using 57 mW of continuous-wave pump. The coincidence to accidental ratio was shown to be limited by spontaneous Raman scattering effects that are expected to be mitigated by using a pulsed pump source., Comment: 3 pages, 4 figures

Published
2010
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9. Advances in chip-based brillouin sources

Author

Australian Conference on Optical Fibre Technology (39th : 2014 : Melbourne), Kabakova, IV, Buttner, TFS, Merklein, M, Choi, D-Y, Madden, S, Luther-Davies, B, and Eggleton, BJ

Published
2014

10. Hybrid Dielectric Metasurfaces for Enhancing Second-Harmonic Generation in Chemical Vapor Deposition Grown MoS2 Monolayers

Author

Löchner, F.J.F., George, A., Koshelev, K., Bucher, T., Najafidehaghani, E., Fedotova, A., Choi, D.-Y., Pertsch, T., Staude, I., Kivshar, Y., Turchanin, A., Setzpfandt, F., and Publica

Subjects
2D Material, dielectric metasurface, Fano resonance, chemical vapor deposition, second-harmonic generation
Abstract

The coupling of two-dimensional materials with optical metasurfaces is a promising avenue to enhance the advantageous properties of both platforms. Here we integrate an ultrathin monolayer of the transition metal dichalcogenide (TMD) MoS2, grown by chemical-vapor deposition, with a silicon metasurface, to obtain a hybrid system with enhanced nonlinear response. To this end, we utilize a metasurface exhibiting resonances with high quality factors, which provides increased optical fields. Using the nonlinearity of the TMD monolayer, these resonantly enhanced fields enable more efficient nonlinear frequency conversion. In particular, we experimentally observe an enhanced efficiency of second-harmonic generation in our hybrid structure. By comparing second-harmonic generation using different photonic resonances, we furthermore identify optimized conditions for the spatial distribution of the local optical fields to maximize the nonlinear response. Our results enable the precise design of hybrid structures consisting from TMDs and metasurfaces for future applications.

Published
2021

13. Quasi-BIC Resonant Enhancement of Second-Harmonic Generation in WS2 Monolayers

Author

Bernhardt, N, Koshelev, K, White, SJU, Meng, KWC, Fröch, JE, Kim, S, Tran, TT, Choi, D-Y, Kivshar, Y, and Solntsev, AS

Subjects
Nanoscience & Nanotechnology
Abstract

Atomically thin monolayers of transition metal dichalcogenides (TMDs) have emerged as a promising class of novel materials for optoelectronics and nonlinear optics. However, the intrinsic nonlinearity of TMD monolayers is weak, limiting their functionalities for nonlinear optical processes such as frequency conversion. Here we boost the effective nonlinear susceptibility of a TMD monolayer by integrating it with a resonant dielectric metasurface that supports pronounced optical resonances with high quality factors: bound states in the continuum (BICs). We demonstrate that a WS2 monolayer combined with a silicon metasurface hosting BICs exhibits enhanced second-harmonic intensity by more than 3 orders of magnitude relative to a WS2 monolayer on top of a flat silicon film of the same thickness. Our work suggests a pathway to employ high-index dielectric metasurfaces as hybrid structures for enhancement of TMD nonlinearities with applications in nonlinear microscopy, optoelectronics, and signal processing.

Published
2020

16. Manipulation of magnetic dipole emission from Eu3+ with Mie-resonant dielectric metasurfaces

Author

Vaskin, A., Mashhadi, S., Steinert, M., Chong, K.E., Keene, D., Nanz, S., Abass, A., Rusak, E., Choi, D.-Y., Fernandez-Corbaton, I., Pertsch, T., Rockstuhl, C., Noginov, M.A., Kivshar, S., Neshev, D.N., Noginova, N., Staude, I., and Publica

Abstract

Mie-resonant high-index dielectric nanoparticles and metasurfaces have been suggested as a viable platform for enhancing both electric and magnetic dipole transitions of fluorescent emitters. While the enhancement of the electric dipole transitions by such dielectric nanoparticles has been demonstrated experimentally, the case of magnetic-dipole transitions remains largely unexplored. Here, we study the enhancement of spontaneous emission of Eu3+ ions, featuring both electric and magnetic-dominated dipole transitions, by dielectric metasurfaces composed of Mie-resonant silicon nanocylinders. By coating the metasurfaces with a layer of an Eu3+ doped polymer, we observe an enhancement of the Eu3+ emission associated with the electric (at 610 nm) and magnetic-dominated (at 590 nm) dipole transitions. The enhancement factor depends systematically on the spectral proximity of the atomic transitions to the Mie resonances as well as their multipolar order, both controlled by the nanocylinder size. Importantly, the branching ratio of emission via the electric or magnetic transition channel can be modified by carefully designing the metasurface, where the magnetic dipole transition is enhanced more than the electric transition for cylinders with radii of about 130 nm. We confirm our observations by numerical simulations based on the reciprocity principle. Our results open new opportunities for bright nanoscale light sources based on magnetic transitions.

Published
2019

18. High-bit rate ultra-compact light routing with mode-selective on-chip nanoantennas

Author

Guo, R., Decker, M., Setzpfandt, F., Gai, X., Choi, D.-Y., Kiselev, R., Chipouline, A., Staude, I., Pertsch, T., Neshev, D.N., Kivshar, Y.S., and Publica

Abstract

Optical nanoantennas provide a promising pathway toward advanced manipulation of light waves, such as directional scattering, polarization conversion, and fluorescence enhancement. Although these functionalities were mainly studied for nanoantennas in free space or on homogeneous substrates, their integration with optical waveguides offers an important ""wired"" connection to other functional optical components. Taking advantage of the nanoantenna's versatility and unrivaled compactness, their imprinting onto optical waveguides would enable a marked enhancement of design freedom and integration density for optical on-chip devices. Several examples of this concept have been demonstrated recently. However, the important question of whether nanoantennas can fulfill functionalities for high-bit rate signal transmission without degradation, which is the core purpose of many integrated optical applications, has not yet been experimentally investigated. We introduce and investigate directional, polarization-selective, and mode-selective on-chip nanoantennas integrated with a silicon rib waveguide. We demonstrate that these nanoantennas can separate optical signals with different polarizations by coupling the different polarizations of light vertically to different waveguide modes propagating into opposite directions. As the central result of this work, we show the suitability of this concept for the control of optical signals with ASK (amplitude-shift keying) NRZ (nonreturn to zero) modulation [10 Gigabit/s (Gb/s)] without significant bit error rate impairments. Our results demonstrate that waveguide-integrated nanoantennas have the potential to be used as ultra-compact polarization-demultiplexing on-chip devices for high-bit rate telecommunication applications.

Published
2017

19. Effect of low-Raman window position on correlated photon-pair generation in a chalcogenide Ge11.5As24Se64.5 nanowire.

Author

He, J., Xiong, C., Clark, A. S., Collins, M. J., Gai, X., Choi, D.-Y., Madden, S. J., Luther-Davies, B., and Eggleton, B. J.

Subjects
PHOTONS, CHALCOGENIDES, NANOWIRES, RAMAN effect, PHONONS
Abstract

We investigated correlated photon-pair generation via spontaneous four-wave mixing in an integrated chalcogenide Ge11.5As24Se64.5 photonic nanowire. The coincidence to accidental ratio, a key measurement for the quality of correlated photon-pair sources, was measured to be only 0.4 when the photon pairs were generated at 1.9 THz detuning from the pump frequency due to high spontaneous Raman noise in this regime. However, the existence of a characteristic low-Raman window at around 5.1 THz in this material's Raman spectrum and dispersion engineering of the nanowire allowed us to generate photon pairs with a coincidence to accidental ratio of 4.5, more than 10 times higher than the 1.9 THz case. Through comparing the results with those achieved in chalcogenide As2S3 waveguides which also exhibit a low Raman-window but at a larger detuning of 7.4 THz, we find that the position of the characteristic low-Raman window plays an important role on reducing spontaneous Raman noise because the phonon population is higher at smaller detuning. Therefore the ultimate solution for Raman noise reduction in Ge11.5As24Se64.5 is to generate photon pairs outside the Raman gain band at more than 10 THz detuning. [ABSTRACT FROM AUTHOR]

Published
2012
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20. Raman spectra of GexAsySe1-x-y glasses.

Author

Wang, R. P., Smith, A., Prasad, A., Choi, D. Y., and Luther-Davies, B.

Subjects
RAMAN effect, GLASS, TRANSITION temperature, GERMANIUM, ARSENIC, SELENIUM, SCATTERING (Physics)
Abstract

Various Ge–As–Se glasses spanning a mean coordination number (MCN) from 2.2 to 2.94 have been investigated using differential scanning calorimetry and Raman spectroscopy. The glass transition temperature Tg was found to increase with increasing MCN, except for those glasses located within the nanoscale phase-separated region of the phase diagram. The evolution of Raman features at wavenumbers from 150 to 350 cm-1 exhibits two transitionlike features. Merging of the 225 and 250 cm-1 modes at MCN=2.5 is a symbol of the extinction of Se–Se bonds. Additionally, the appearance of two modes at 280–290 and 170 cm-1 at MCN>2.7 come from the defect modes of ethanelike Ge2Se6/2. The increase in the scattering from these defects is an important factor leading to enhanced optical loss in the glasses with high MCN. [ABSTRACT FROM AUTHOR]

Published
2009
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21. Annealing-induced reduction in nanoscale heterogeneity of thermally evaporated amorphous As2S3 films.

Author

Liu, A. C. Y., Chen, Xidong, Choi, D.-Y., and Luther-Davies, B.

Subjects
ANNEALING of crystals, ARSENIDES, ARSENIC compounds, ORPIMENT, TRANSMISSION electron microscopy, METALLIC films
Abstract

The morphology and structural order of thermally deposited and annealed amorphous As2S3 films have been investigated using high resolution transmission electron microscopy. It was found that both the as-deposited and annealed films contained sparsely distributed nanocrystallites of the orpiment As2S3 crystalline phase. However, from selected area electron diffraction both films appeared amorphous. Fluctuation electron microscopy revealed that the as-deposited film contained greater nanoscale inhomogeneity. Low temperature annealing reduced the nanoscale inhomogeneity and resulted in a more homogeneous and energetically favorable network. The reduction in nanoscale inhomogeneity upon low temperature annealing was accompanied by the appearance of a first sharp diffraction peak in the diffraction pattern. This first-sharp diffraction peak has been attributed to chemical ordering of interstitial voids. Our measurements suggest that this chemical short-range ordering is associated with the dissolution of the energetically unfavorable larger correlated structures that contribute to the inhomogeneity of the as-deposited film. [ABSTRACT FROM AUTHOR]

Published
2008
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22. Investigation of the structure of GexAsySe1-x-y glasses by x-ray photoelectron spectroscopy.

Author

Wang, R. P., Rode, A. V., Choi, D. Y., and Luther-Davies, B.

Subjects
X-ray photoelectron spectroscopy, SPECTRUM analysis, GLASS, VALENCE (Chemistry), COMPOSITE materials
Abstract

We have measured and analyzed x-ray photoelectron spectra of a series of GexAsySe1-x-y glasses. The valence band spectra show that a number of Se-rich structures exist in the samples. After decomposing Ge, As, and Se 3d spectra into several doublets and assigning them to the different local bond structures, it was found that, while GeSe4/2 tetrahedral, AsSe3/2 pyramidal, and Se trimers decrease in their integrated areas, most defect bonds increase with increasing mean coordination number. Moreover, while the appearance of Se trimers is reasonable in Se-rich samples, they never vanish, even in Se-poor samples. A possible mechanism to form Se trimers in Se-poor samples is discussed. [ABSTRACT FROM AUTHOR]

Published
2008
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23. Rebonding of Se to As and Ge in Ge33As12Se55 films upon thermal annealing: Evidence from x-ray photoelectron spectra investigations.

Author

Wang, R. P., Choi, D. Y., Rode, A. V., Madden, S. J., and Luther-Davies, B.

Subjects
*GERMANIUM, *ARSENIC, *SELENIUM, *THIN films, *X-ray photoelectron spectroscopy, *HIGH temperatures, *BULK solids, *OXIDATION
Abstract

We have measured and analyzed x-ray photoelectron spectra (XPS) of as-grown and annealed Ge33As12Se55 films compared with bulk material. We found that the as-grown film contains a large number of separated Se clusters which can coalesce with As and Ge after annealing at high temperatures. In addition, both the Ge and As 3d spectra show the presence of oxides. While the Ge oxidation increases with an increasing annealing temperature, As oxidation is almost unaffected by annealing. The difference could be due to their different electro-negativities. Our results suggest that, while thermal annealing is effective to move the film toward the bond structure of bulk glass, the simultaneous surface oxidation must be suppressed in order to achieve high quality films. [ABSTRACT FROM AUTHOR]

Published
2007
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24. Formation of plasma induced surface damage in silica glass etching for optical waveguides.

Author

Choi, D. Y., Lee, J. H., Kim, D. S., and Jung, S. T.

Subjects
*SILICA, *GLASS, *OPTICAL fibers, *PLASMA gases, *ETCHING, *IONS, *PHYSICS
Abstract

Ge, B, P-doped silica glass films are widely used as optical waveguides because of their low losses and inherent compatibility with silica optical fibers. These films were etched by ICP (inductively coupled plasma) with chrome etch masks, which were patterned by reactive ion etching (RIE) using chlorine-based gases. In some cases, the etched surfaces of silica glass were very rough (root-mean square roughness greater than 100 nm) and we call this phenomenon plasma induced surface damage (PISD). Rough surface cannot be used as a platform for hybrid integration because of difficulty in alignment and bonding of active devices. PISD reduces the etch rate of glass and it is very difficult to remove residues on a rough surface. The objective of this study is to elucidate the mechanism of PISD formation. To achieve this goal, PISD formation during different etching conditions of chrome etch mask and silica glass was investigated. In most cases, PISD sources are formed on a glass surface after chrome etching, and metal compounds are identified in theses sources. Water rinse after chrome etching reduces the PISD, due to the water solubility of metal chlorides. PISD is decreased or even disappeared at high power and/or low pressure in glass etching, even if PISD sources were present on the glass surface before etching. In conclusion, PISD sources come from the chrome etching process, and polymer deposition on these sources during the silica etching cause the PISD sources to grow. In the area close to the PISD source there is a higher ion flux, which causes an increase in the etch rate, and results in the formation of a pit. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Published
2004
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25. Polarization-Controlled Broad Color Palette Based on an Ultrathin One-Dimensional Resonant Grating Structure

Author

Koirala, I, Shrestha, VR, Park, C-S, Lee, S-S, Choi, D-Y, Koirala, I, Shrestha, VR, Park, C-S, Lee, S-S, and Choi, D-Y

Abstract

Highly efficient polarization-tuned structural color filters, which are based on a one- dimensional resonant aluminum grating that is integrated with a silicon nitride waveguide, are proposed and demonstrated to feature a broad color palette. For such a metallic grating structure, transmissive color filtering is only feasible for the incident transverse-magnetic (TM) polarization due to its high reflection regarding the transverse-electric (TE) case; however, polarization-tuned customized colors can be efficiently achieved by optimizing the structural parameters like the duty ratio of the metallic grating. For the fabricated color filters, the transmission peaks, which are imputed to the resonance between the incident light and the guided modes that are supported by the dielectric waveguide, provided efficiencies as high as 90% and 70% for the TM and TE polarizations, respectively, as intended. Through the tailoring of the polarization, a group of filters with different grating periods were successfully exploited to produce a broad color palette spanning the entire visible band. Lastly, a nanoscale alphabetic pattern featuring a flexible combination of colorations was practically constructed via an arrangement of horizontal and vertical gratings.

Published
2017

26. Structural Color Filters Enabled by a Dielectric Metasurface Incorporating Hydrogenated Amorphous Silicon Nanodisks

Author

Park, C-S, Shrestha, VR, Yue, W, Gao, S, Lee, S-S, Kim, E-S, Choi, D-Y, Park, C-S, Shrestha, VR, Yue, W, Gao, S, Lee, S-S, Kim, E-S, and Choi, D-Y

Abstract

It is advantageous to construct a dielectric metasurface in silicon due to its compatibility with cost-effective, mature processes for complementary metal-oxide-semiconductor devices. However, high-quality crystalline-silicon films are difficult to grow on foreign substrates. In this work, we propose and realize highly efficient structural color filters based on a dielectric metasurface exploiting hydrogenated amorphous silicon (a-Si:H), known to be lossy in the visible regime. The metasurface is comprised of an array of a-Si:H nanodisks embedded in a polymer, providing a homogeneously planarized surface that is crucial for practical applications. The a-Si:H nanodisk element is deemed to individually support an electric dipole (ED) and magnetic dipole (MD) resonance via Mie scattering, thereby leading to wavelength-dependent filtering characteristics. The ED and MD can be precisely identified by observing the resonant field profiles with the assistance of finite-difference time-domain simulations. The completed color filters provide a high transmission of around 90% in the off-resonance band longer than their resonant wavelengths, exhibiting vivid subtractive colors. A wide range of colors can be facilitated by tuning the resonance by adjusting the structural parameters like the period and diameter of the a-Si:H nanodisk. The proposed devices will be actively utilized to implement color displays, imaging devices, and photorealistic color printing.

Published
2017

27. All Dielectric Transmissive Structural Multicolor Pixel Incorporating a Resonant Grating in Hydrogenated Amorphous Silicon

Author

Koirala, I, Shrestha, VR, Park, C-S, Gao, S, Lee, S-S, Choi, D-Y, Koirala, I, Shrestha, VR, Park, C-S, Gao, S, Lee, S-S, and Choi, D-Y

Abstract

All dielectric transmissive type polarization-tuned structural multicolor pixels (MCPs) are proposed and demonstrated based on a one-dimensional hydrogenated amorphous silicon (a-Si:H) grating integrated with a silicon nitride waveguide. Both bandpass and bandstop transmission filtering characteristics in the visible regime, centered at the same wavelength, have been achieved by tailoring the structural parameters including the duty ratio of the grating and the thickness of the dielectric waveguide. For the three manufactured MCPs, the transmission peak exceeds 70% for the transverse electric (TE) polarization and 90% for the transverse magnetic (TM) polarization as observed at the resonance and off-resonance wavelength, respectively. The polarization-switched transmissions are attributed to the guided mode resonance initiated by the interaction of the a-Si:H grating and the dielectric waveguide. A broad color palette covering the entire visible band was successfully realized from a suite of MCPs with varying grating pitches. The proposed structural color pixels are expected to facilitate the construction of dynamic displays, image sensors, optical data storage, security tags, and so forth.

Published
2017

28. Enhanced second-harmonic generation from two-dimensional MoSe2 on a silicon waveguide.

Author

Chen, H, Corboliou, V, Solntsev, AS, Choi, D-Y, Vincenti, MA, de Ceglia, D, de Angelis, C, Lu, Y, Neshev, DN, Chen, H, Corboliou, V, Solntsev, AS, Choi, D-Y, Vincenti, MA, de Ceglia, D, de Angelis, C, Lu, Y, and Neshev, DN

Abstract

Two-dimensional transition-metal dichalcogenides (TMDCs) with intrinsically broken crystal inversion symmetry and large second-order nonlinear responses have shown great promise for future nonlinear light sources. However, the sub-nanometer monolayer thickness of such materials limits the length of their nonlinear interaction with light. Here, we experimentally demonstrate the enhancement of the second-harmonic generation from monolayer MoSe2 by its integration onto a 220-nm-thick silicon waveguide. Such on-chip integration allows for a marked increase in the interaction length between the MoSe2 and the waveguide mode, further enabling phase matching of the nonlinear process. The demonstrated TMDC-silicon photonic hybrid integration opens the door to second-order nonlinear effects within the silicon photonic platform, including efficient frequency conversion, parametric amplification and the generation of entangled photon pairs.

Published
2017

29. Overview of the TCV tokamak program: scientific progress and facility upgrades

Author

Coda, S., Ahn, J., Albanese, R., Alberti, S., Alessi, E., Allan, Jonathan S., Anand, H., Anastassiou, G., Andrèbe, Y., Angioni, C., Ariola, M., Bernert, M., Beurskens, M., Bin Najib, Waqas, Blanchard, P., Blanken, T. C., Boedo, J. A., Bolzonella, T., Bouquey, F., Braunmüller, F. H., Bufferand, H., Buratti, P, Calabró, G., Camenen, Y., Carnevale, D., Carpanese, F., Causa, F., Cesario, R., Chapman, I.T., Chellai, O., Choi, D-Y., Cianfarani, C., Ciraolo, G., Citrin, J, Costea, S., Crisanti, F, Cruz, N., Czarnecka, A., Decker, J., De Masi, G., De Tommasi, G., Douai, D., Dunne, M., Duval, B. P., Eich, T., Elmore, S., Esposito, B., Faitsch, M., Fasoli, A., Fedorczak, N., Felici, F., Février, O., Ficker, O., Fietz, S., Fontana, M., Frassinetti, L, Furno, I., Galeani, S., Gallo, Antonio, Galperti, C., Garavaglia, S., Garrido, I., Geiger, B., Giovannozzi, E., Gobbin, M., Goodman, T.P., Gorini, G., Gospodarczyk, M., Granucci, G., Graves, J.P., Guirlet, R., Hakola, A.H., Ham, C., Harrison, J., Hawke, J., Hennequin, P., Hnat, B., Hogeweij, G.M.D., Hogge, J.-Ph, Honoré, C., Hopf, C., Horáček, J., Huang, Zhiwei, Igochine, V., Innocente, P., Schrittwieser, C. Ionita, Isliker, H., Jacquier, R., Jardin, A., Kamleitner, J., Karpushov, A., Keeling, D.L., Kirneva, N., Kong, M., Koubiti, M., Kovacic, J., Krämer-Flecken, A., Krawczyk, N., Kudlacek, O., Labit, B., Lazzaro, Enzo, Le, H.B., Lipschultz, B., Llobet, X., Lomanowski, B., Loschiavo, V.P., Lunt, T., Maget, P., Maljaars, E., Malygin, S.A., Maraschek, M., Marini, C., Martin, P., Martin, Y., Mastrostefano, S., Maurizio, R., Mavridis, M., Mazon, D., McAdams, R., McDermott, R., Merle, A., Meyer, H., Militello, F., Miron, I.G., Molina Cabrera, P. A., Moret, J.-M., Del Moro, A., Moulton, D., Naulin, Volker, Nespoli, F., Nielsen, Anders Henry, Nocente, M., Nouailletas, R., Nowak, S., Odstrčil, T., Papp, G., Papřok, R., Pau, A., Pautasso, G., Pericoli Ridolfini, V., Piovesan, P., Piron, C., Pisokas, T., Porte, L., Preynas, M., Ramogida, G., Rapson, C., Rasmussen, Jens Juul, Reich, M., Reimerdes, H., Reux, C., Ricci, P., Rittich, D., Riva, F., Robinson, T., Saarelma, S., Saint-Laurent, F., Sauter, O., Scannell, R., Schlatter, C., Schneider, B., Schneider, P., Schrittwieser, R., Sciortino, Natasha F., Sertoli, M., Sheikh, U., Sieglin, B., Silva, M., Sinha, J., Sozzi, C, Spolaore, M., Stange, T., Stoltzfus-Dueck, T., Tamain, P., Teplukhina, A., Testa, D., Theiler, C., Thornton, A., Tophøj, Laust Emil Hjerrild, Tran, M. Q., Tsironis, C., Tsui, C., Uccello, A., Vartanian, S., Verdoolaege, G., Verhaegh, K., Vermare, L., Vianello, N., Vijvers, W.A.J., Vlahos, L., Vu, N.M.T., Walkden, N. R., Wauters, T., Weisen, H., Wischmeier, M., Zestanakis, P., Zuin, Matteo, Coda, S., Ahn, J., Albanese, R., Alberti, S., Alessi, E., Allan, Jonathan S., Anand, H., Anastassiou, G., Andrèbe, Y., Angioni, C., Ariola, M., Bernert, M., Beurskens, M., Bin Najib, Waqas, Blanchard, P., Blanken, T. C., Boedo, J. A., Bolzonella, T., Bouquey, F., Braunmüller, F. H., Bufferand, H., Buratti, P, Calabró, G., Camenen, Y., Carnevale, D., Carpanese, F., Causa, F., Cesario, R., Chapman, I.T., Chellai, O., Choi, D-Y., Cianfarani, C., Ciraolo, G., Citrin, J, Costea, S., Crisanti, F, Cruz, N., Czarnecka, A., Decker, J., De Masi, G., De Tommasi, G., Douai, D., Dunne, M., Duval, B. P., Eich, T., Elmore, S., Esposito, B., Faitsch, M., Fasoli, A., Fedorczak, N., Felici, F., Février, O., Ficker, O., Fietz, S., Fontana, M., Frassinetti, L, Furno, I., Galeani, S., Gallo, Antonio, Galperti, C., Garavaglia, S., Garrido, I., Geiger, B., Giovannozzi, E., Gobbin, M., Goodman, T.P., Gorini, G., Gospodarczyk, M., Granucci, G., Graves, J.P., Guirlet, R., Hakola, A.H., Ham, C., Harrison, J., Hawke, J., Hennequin, P., Hnat, B., Hogeweij, G.M.D., Hogge, J.-Ph, Honoré, C., Hopf, C., Horáček, J., Huang, Zhiwei, Igochine, V., Innocente, P., Schrittwieser, C. Ionita, Isliker, H., Jacquier, R., Jardin, A., Kamleitner, J., Karpushov, A., Keeling, D.L., Kirneva, N., Kong, M., Koubiti, M., Kovacic, J., Krämer-Flecken, A., Krawczyk, N., Kudlacek, O., Labit, B., Lazzaro, Enzo, Le, H.B., Lipschultz, B., Llobet, X., Lomanowski, B., Loschiavo, V.P., Lunt, T., Maget, P., Maljaars, E., Malygin, S.A., Maraschek, M., Marini, C., Martin, P., Martin, Y., Mastrostefano, S., Maurizio, R., Mavridis, M., Mazon, D., McAdams, R., McDermott, R., Merle, A., Meyer, H., Militello, F., Miron, I.G., Molina Cabrera, P. A., Moret, J.-M., Del Moro, A., Moulton, D., Naulin, Volker, Nespoli, F., Nielsen, Anders Henry, Nocente, M., Nouailletas, R., Nowak, S., Odstrčil, T., Papp, G., Papřok, R., Pau, A., Pautasso, G., Pericoli Ridolfini, V., Piovesan, P., Piron, C., Pisokas, T., Porte, L., Preynas, M., Ramogida, G., Rapson, C., Rasmussen, Jens Juul, Reich, M., Reimerdes, H., Reux, C., Ricci, P., Rittich, D., Riva, F., Robinson, T., Saarelma, S., Saint-Laurent, F., Sauter, O., Scannell, R., Schlatter, C., Schneider, B., Schneider, P., Schrittwieser, R., Sciortino, Natasha F., Sertoli, M., Sheikh, U., Sieglin, B., Silva, M., Sinha, J., Sozzi, C, Spolaore, M., Stange, T., Stoltzfus-Dueck, T., Tamain, P., Teplukhina, A., Testa, D., Theiler, C., Thornton, A., Tophøj, Laust Emil Hjerrild, Tran, M. Q., Tsironis, C., Tsui, C., Uccello, A., Vartanian, S., Verdoolaege, G., Verhaegh, K., Vermare, L., Vianello, N., Vijvers, W.A.J., Vlahos, L., Vu, N.M.T., Walkden, N. R., Wauters, T., Weisen, H., Wischmeier, M., Zestanakis, P., and Zuin, Matteo

Abstract

The TCV tokamak is augmenting its unique historical capabilities (strong shaping, strong electron heating) with ion heating, additional electron heating compatible with high densities, and variable divertor geometry, in a multifaceted upgrade program designed to broaden its operational range without sacrificing its fundamental flexibility. The TCV program is rooted in a three-pronged approach aimed at ITER support, explorations towards DEMO, and fundamental research. A 1 MW, tangential neutral beam injector (NBI) was recently installed and promptly extended the TCV parameter range, with record ion temperatures and toroidal rotation velocities and measurable neutral-beam current drive. ITER-relevant scenario development has received particular attention, with strategies aimed at maximizing performance through optimized discharge trajectories to avoid MHD instabilities, such as peeling-ballooning and neoclassical tearing modes. Experiments on exhaust physics have focused particularly on detachment, a necessary step to a DEMO reactor, in a comprehensive set of conventional and advanced divertor concepts. The specific theoretical prediction of an enhanced radiation region between the two X-points in the low-field-side snowflake-minus configuration was experimentally confirmed. Fundamental investigations of the power decay length in the scrape-off layer (SOL) are progressing rapidly, again in widely varying configurations and in both D and He plasmas; in particular, the double decay length in L-mode limited plasmas was found to be replaced by a single length at high SOL resistivity. Experiments on disruption mitigation by massive gas injection and electron-cyclotron resonance heating (ECRH) have begun in earnest, in parallel with studies of runaway electron generation and control, in both stable and disruptive conditions; a quiescent runaway beam carrying the entire electrical current appears to develop in some cases. Developments in plasma control have benefited from pr

Published
2017

30. Overview of progress in European medium sized tokamaks towards an integrated plasma-edge/wall solution

Author

Meyer, H., Eich, T., Beurskens, M., Coda, S., Hakola, A.H., Martin, P., Adamek, J., Agostini, M., Aguiam, D., Ahn, J., Aho-Mantila, L., Akers, R., Albanese, R., Aledda, R., Alessi, E., Allan, Jonathan S., da Costa Alves Machado, Simone, Ambrosino, R., Amicucci, L., Anand, H., Anastassiou, G., Andrèbe, Y., Angioni, C., Apruzzese, G., Ariola, M., Arnichand, H., Arter, W., Baciero, A., Barnes, M., Barrera Orte, L., Behn, R., Bencze, A., Bernardo, J., Bernert, M., Bettini, P., Bílková, P., Bin Najib, Waqas, Birkenmeier, G., Bizarro, J P S, Blanchard, P., Blanken, T., Bluteau, M., Bobkov, V., Bogar, O., Böhm, P., Bolzonella, T., Boncagni, L., Botrugno, A., Bottereau, C., Bouquey, F., Bourdelle, C., Bremond, S., Brezinsek, S., Brida, D., Brochard, F., Buchanan, F.J., Bufferand, H., Buratti, P, Cahyna, P., Calabro, G., Camenen, Y., Caniello, R., Cannas, B., Canton, A., Cardinali, A., Carnevale, D., Carr, Meghan, Carralero, D., Carvalho, P., Casali, L., Castaldo, C., Castejón, F., Castro, R., Causa, F., Cavazzana, R., Cavedon, M., Cecconello, M., Ceccuzzi, S., Cesario, R., Challis, C.D., Chapman, I.T., Chapman, S.C., Chernyshova, M., Choi, D-Y., Cianfarani, C., Ciraolo, G., Citrin, J, Clairet, F., Classen, I., Coelho, R., Coenen, J.W., Colas, L., Conway, G., Corre, Y., Costea, S., Crisanti, F, Cruz, N., Cseh, G., Czarnecka, A., D’Arcangelo, O., De Angeli, M., De Masi, G., De Temmerman, G., De Tommasi, G., Decker, J., Delogu, R.S., Dendy, R.O., Denner, P., Di Troia, C., Dimitrova, M., D’Inca, R., Dorić, V., Douai, D., Drenik, A., Dudson, B., Dunai, D., Dunne, M., Duval, B. P., Easy, L., Elmore, S., Erdös, B., Esposito, B., Fable, E., Faitsch, M., Fanni, A., Fedorczak, N., Felici, F., Ferreira, J., Février, O., Ficker, O., Fietz, S., Figini, L., Figueiredo, A., Fil, A., Fishpool, G., FitzGerald, Michael, Fontana, M., Ford, O., Frassinetti, L, Fridström, R., Frigione, D., Fuchert, G., Fuchs, C., Furno Palumbo, M., Futatani, S., Gabellieri, L., Gałązka, K., Galdon-Quiroga, J., Galeani, S., Gallart, D., Gallo, Antonio, Galperti, C., Gao, Y., Garavaglia, S., Garcia, J., Garcia-Carrasco, A., Garcia Lopez, J., García-Muñoz, M., Gardarein, J.-L., Garzotti, L., Gaspar, J., Gauthier, E., Geelen, P., Geiger, B., Ghendrih, P., Ghezzi, F., Giacomelli, L., Giannone, L., Giovannozzi, E., Giroud, C., Gleason González, C., Gobbin, M., Goodman, T.P., Gorini, G., Gospodarczyk, M., Granucci, G., Gruber, M., Gude, A., Guimarais, L., Guirlet, R., Gunn, George J., Hacek, P., Hacquin, S., Hall, S., Ham, C., Happel, T., Harrison, J., Harting, D., Hauer, V., Havlícková, E., Hellsten, T., Helou, W., Henderson, S.S., Hennequin, P., Heyn, M., Hnat, B., Hölzl, M., Hogeweij, G.M.D., Honoré, Connie, Hopf, C., Horáček, J., Hornung, G., Horvath, L., Huang, Zhiwei, Huber, Andreas, Igitkhanov, J., Igochine, V., Imrisek, M., Innocente, P., Ionita-Schrittwieser, C., Isliker, H., Ivanova-Stanik, I., Jacobsen, Asger Schou, Jacquet, P., Jakubowski, M., Jardin, A., Jaulmes, F., Jenko, F., Jensen, Thomas, Olsen, Jeppe Miki Busk, Jessen, Martin, Joffrin, E., Jones, O., Jónsson, T., Kallenbach, A., Kallinikos, N., Kalvin, S., Kappatou, A., Karhunen, J., Karpushov, A., Kasilov, S., Kasprowicz, G., Kendl, A., Kernbichler, W., Kim, D., Kirk, A., Kjer, S., Klimek, I., Kocsis, G., Kogut, D., Komm, M., Korsholm, Søren Bang, Koslowski, H R, Koubiti, M., Kovacic, J., Kovarik, K., Krawczyk, N., Krbec, J., Krieger, K., Krivska, A., Kube, R., Kudlacek, O., Kurki-Suonio, T., Labit, B., Laggner, F.M., Laguardia, L., Lahtinen, Annukka M, Lalousis, P., Lang, P.T., Lauber, P., Lazanyi, N., Lazaros, A., Le, H.B., Lebschy, A., Leddy, J., Lefèvre, Laure, Lehnen, M., Leipold, Frank, Lessig, A., Leyland, M., Li, L., Liang, Y., Lipschultz, B., Liu, Y.Q., Loarer, T., Loarte, A., Loewenhoff, T., Lomanowski, B., Loschiavo, V.P., Lunt, T., Lupelli, I., Lux, H., Lyssoivan, A., Madsen, Jens, Maget, P., Maggi, C., Maggiora, R., Magnussen, Michael Løiten, Mailloux, J., Maljaars, B., Malygin, S.A., Mantica, P., Mantsinen, M., Maraschek, M., Marchand, B., Marconato, N., Marini, C., Marinucci, M., Markovic, T., Marocco, D., Marrelli, L., Martin, Y., Martín-Solís, J. R., Martitsch, A., Mastrostefano, S., Mattei, M., Matthews, G.F., Mavridis, M., Mayoral, M.-L., Mazon, D., McCarthy, P., McAdams, R., McArdle, G.J., McClements, K.G., McDermott, R., McMillan, B., Meisl, G., Merle, A., Meyer, O., Milanesio, D., Militello, F., Miron, I.G., Mitosinkova, K., Mlynar, J., Mlynek, A., Molina, Daniel R., Molina, Pablo, Monakhov, I., Morales, J.M., Moreau, Debra L., Morel, P., Moret, J.-M., Del Moro, A., Moulton, D., Müller, H.W., Nabais, F., Nardon, E., Naulin, Volker, Nemes-Czopf, A., Nespoli, F., Neu, R., Nielsen, Anders Henry, Nielsen, Stefan Kragh, Nikolaeva, V., Nimb, Søren Robert, Nocente, M., Nouailletas, R., Nowak, S., Oberkofler, M., Oberparleiter, M., Ochoukov, R., Odstrčil, T., Olsen, J., Omotani, J., O’Mullane, M.G., Orain, F., Osterman, N., Paccagnella, R., Pamela, S., Pangione, L., Panjan, M., Papp, G., Papřok, R., Parail, V., Parra, F.I., Pau, A., Pautasso, G., Pehkonen, S.-P., Pereira, A., Perelli Cippo, Enrico, Pericoli Ridolfini, V., Peterka, M., Petersson, P., Petrzilka, V., Piovesan, P., Piron, C., Pironti, A., Pisano, F., Pisokas, T., Pitts, R., Ploumistakis, I., Plyusnin, V., Pokol, G., Poljak, D., Pölöskei, P., Popovic, Z., Pór, G., Porte, L., Potzel, S., Predebon, I., Preynas, M., Primc, G., Pucella, Gianluca, Puiatti, M.E., Pütterich, T., Rack, M., Ramogida, G., Rapson, C., Rasmussen, Jens Juul, Rasmussen, Jesper, Rattá, G.A., Ratynskaia, S., Ravera, G., Réfy, D., Reich, M., Reimerdes, H., Reimold, F., Reinke, M., Reiser, D., Resnik, M., Reux, C., Ripamonti, D., Rittich, D., Riva, G., Rodriguez-Ramos, M., Rohde, V., Rosato, J., Ryter, F., Saarelma, S., Sabot, R., Saint-Laurent, F., Salewski, Mirko, Salmi, A., Samaddar, D., Sanchis-Sanchez, L., Santos, J., Sauter, O., Scannell, R., Scheffer, M., Schneider, M., Schneider, B., Schneider, P., Schneller, M., Schrittwieser, R., Schubert, M., Schweinzer, J., Seidl, J., Sertoli, M., Šesnić, S., Shabbir, A., Shalpegin, A., Shanahan, B., Sharapov, S., Sheikh, U., Sias, G., Sieglin, B., Silva, C., Silva, A., Silva Fuglister, M., Simpson, James J., Snicker, A., Sommariva, C., Sozzi, C, Spagnolo, S., Spizzo, G., Spolaore, M., Stange, T., Pedersen, Morten Stejner, Stepanov, I., Stober, J., Strand, P., Šušnjara, A., Suttrop, W., Szepesi, T., Tál, B., Tala, T., Tamain, P., Tardini, G., Tardocchi, M., Teplukhina, A., Terranova, D., Testa, D., Theiler, C., Thornton, A., Tolias, P., Tophøj, Laust Emil Hjerrild, Treutterer, W., Trevisan, G.L., Tripsky, M., Tsironis, C., Tsui, C., Tudisco, O., Uccello, A., Urban, Jesper, Valisa, M., Vallejos, Paul, Valovic, M., van den Brand, H., Vanovac, B., Varoutis, S., Vartanian, S., Vega-Castillo, Jesús, Verdoolaege, G., Verhaegh, K., Vermare, L., Vianello, N., Vicente, J., Viezzer, E., Vignitchouk, L., Vijvers, W.A.J., Villone, F., Viola, B., Vlahos, L., Voitsekhovitch, I., Vondráček, P., Vu, N.M.T., Wágner, D., Walkden, N. R., Wang, N., Wauters, T., Weiland, M., Weinzettl, V., Westerhof, E., Wiesenberger, M., Willensdorfer, M., Wischmeier, M., Wodniak, I., Wolfrum, E., Yadykin, D., Zagorski, R., Zammuto, I., Zanca, P., Zaplotnik, R., Zestanakis, P., Zhang, W., Zoletnik, S., Zuin, Matteo, Meyer, H., Eich, T., Beurskens, M., Coda, S., Hakola, A.H., Martin, P., Adamek, J., Agostini, M., Aguiam, D., Ahn, J., Aho-Mantila, L., Akers, R., Albanese, R., Aledda, R., Alessi, E., Allan, Jonathan S., da Costa Alves Machado, Simone, Ambrosino, R., Amicucci, L., Anand, H., Anastassiou, G., Andrèbe, Y., Angioni, C., Apruzzese, G., Ariola, M., Arnichand, H., Arter, W., Baciero, A., Barnes, M., Barrera Orte, L., Behn, R., Bencze, A., Bernardo, J., Bernert, M., Bettini, P., Bílková, P., Bin Najib, Waqas, Birkenmeier, G., Bizarro, J P S, Blanchard, P., Blanken, T., Bluteau, M., Bobkov, V., Bogar, O., Böhm, P., Bolzonella, T., Boncagni, L., Botrugno, A., Bottereau, C., Bouquey, F., Bourdelle, C., Bremond, S., Brezinsek, S., Brida, D., Brochard, F., Buchanan, F.J., Bufferand, H., Buratti, P, Cahyna, P., Calabro, G., Camenen, Y., Caniello, R., Cannas, B., Canton, A., Cardinali, A., Carnevale, D., Carr, Meghan, Carralero, D., Carvalho, P., Casali, L., Castaldo, C., Castejón, F., Castro, R., Causa, F., Cavazzana, R., Cavedon, M., Cecconello, M., Ceccuzzi, S., Cesario, R., Challis, C.D., Chapman, I.T., Chapman, S.C., Chernyshova, M., Choi, D-Y., Cianfarani, C., Ciraolo, G., Citrin, J, Clairet, F., Classen, I., Coelho, R., Coenen, J.W., Colas, L., Conway, G., Corre, Y., Costea, S., Crisanti, F, Cruz, N., Cseh, G., Czarnecka, A., D’Arcangelo, O., De Angeli, M., De Masi, G., De Temmerman, G., De Tommasi, G., Decker, J., Delogu, R.S., Dendy, R.O., Denner, P., Di Troia, C., Dimitrova, M., D’Inca, R., Dorić, V., Douai, D., Drenik, A., Dudson, B., Dunai, D., Dunne, M., Duval, B. P., Easy, L., Elmore, S., Erdös, B., Esposito, B., Fable, E., Faitsch, M., Fanni, A., Fedorczak, N., Felici, F., Ferreira, J., Février, O., Ficker, O., Fietz, S., Figini, L., Figueiredo, A., Fil, A., Fishpool, G., FitzGerald, Michael, Fontana, M., Ford, O., Frassinetti, L, Fridström, R., Frigione, D., Fuchert, G., Fuchs, C., Furno Palumbo, M., Futatani, S., Gabellieri, L., Gałązka, K., Galdon-Quiroga, J., Galeani, S., Gallart, D., Gallo, Antonio, Galperti, C., Gao, Y., Garavaglia, S., Garcia, J., Garcia-Carrasco, A., Garcia Lopez, J., García-Muñoz, M., Gardarein, J.-L., Garzotti, L., Gaspar, J., Gauthier, E., Geelen, P., Geiger, B., Ghendrih, P., Ghezzi, F., Giacomelli, L., Giannone, L., Giovannozzi, E., Giroud, C., Gleason González, C., Gobbin, M., Goodman, T.P., Gorini, G., Gospodarczyk, M., Granucci, G., Gruber, M., Gude, A., Guimarais, L., Guirlet, R., Gunn, George J., Hacek, P., Hacquin, S., Hall, S., Ham, C., Happel, T., Harrison, J., Harting, D., Hauer, V., Havlícková, E., Hellsten, T., Helou, W., Henderson, S.S., Hennequin, P., Heyn, M., Hnat, B., Hölzl, M., Hogeweij, G.M.D., Honoré, Connie, Hopf, C., Horáček, J., Hornung, G., Horvath, L., Huang, Zhiwei, Huber, Andreas, Igitkhanov, J., Igochine, V., Imrisek, M., Innocente, P., Ionita-Schrittwieser, C., Isliker, H., Ivanova-Stanik, I., Jacobsen, Asger Schou, Jacquet, P., Jakubowski, M., Jardin, A., Jaulmes, F., Jenko, F., Jensen, Thomas, Olsen, Jeppe Miki Busk, Jessen, Martin, Joffrin, E., Jones, O., Jónsson, T., Kallenbach, A., Kallinikos, N., Kalvin, S., Kappatou, A., Karhunen, J., Karpushov, A., Kasilov, S., Kasprowicz, G., Kendl, A., Kernbichler, W., Kim, D., Kirk, A., Kjer, S., Klimek, I., Kocsis, G., Kogut, D., Komm, M., Korsholm, Søren Bang, Koslowski, H R, Koubiti, M., Kovacic, J., Kovarik, K., Krawczyk, N., Krbec, J., Krieger, K., Krivska, A., Kube, R., Kudlacek, O., Kurki-Suonio, T., Labit, B., Laggner, F.M., Laguardia, L., Lahtinen, Annukka M, Lalousis, P., Lang, P.T., Lauber, P., Lazanyi, N., Lazaros, A., Le, H.B., Lebschy, A., Leddy, J., Lefèvre, Laure, Lehnen, M., Leipold, Frank, Lessig, A., Leyland, M., Li, L., Liang, Y., Lipschultz, B., Liu, Y.Q., Loarer, T., Loarte, A., Loewenhoff, T., Lomanowski, B., Loschiavo, V.P., Lunt, T., Lupelli, I., Lux, H., Lyssoivan, A., Madsen, Jens, Maget, P., Maggi, C., Maggiora, R., Magnussen, Michael Løiten, Mailloux, J., Maljaars, B., Malygin, S.A., Mantica, P., Mantsinen, M., Maraschek, M., Marchand, B., Marconato, N., Marini, C., Marinucci, M., Markovic, T., Marocco, D., Marrelli, L., Martin, Y., Martín-Solís, J. R., Martitsch, A., Mastrostefano, S., Mattei, M., Matthews, G.F., Mavridis, M., Mayoral, M.-L., Mazon, D., McCarthy, P., McAdams, R., McArdle, G.J., McClements, K.G., McDermott, R., McMillan, B., Meisl, G., Merle, A., Meyer, O., Milanesio, D., Militello, F., Miron, I.G., Mitosinkova, K., Mlynar, J., Mlynek, A., Molina, Daniel R., Molina, Pablo, Monakhov, I., Morales, J.M., Moreau, Debra L., Morel, P., Moret, J.-M., Del Moro, A., Moulton, D., Müller, H.W., Nabais, F., Nardon, E., Naulin, Volker, Nemes-Czopf, A., Nespoli, F., Neu, R., Nielsen, Anders Henry, Nielsen, Stefan Kragh, Nikolaeva, V., Nimb, Søren Robert, Nocente, M., Nouailletas, R., Nowak, S., Oberkofler, M., Oberparleiter, M., Ochoukov, R., Odstrčil, T., Olsen, J., Omotani, J., O’Mullane, M.G., Orain, F., Osterman, N., Paccagnella, R., Pamela, S., Pangione, L., Panjan, M., Papp, G., Papřok, R., Parail, V., Parra, F.I., Pau, A., Pautasso, G., Pehkonen, S.-P., Pereira, A., Perelli Cippo, Enrico, Pericoli Ridolfini, V., Peterka, M., Petersson, P., Petrzilka, V., Piovesan, P., Piron, C., Pironti, A., Pisano, F., Pisokas, T., Pitts, R., Ploumistakis, I., Plyusnin, V., Pokol, G., Poljak, D., Pölöskei, P., Popovic, Z., Pór, G., Porte, L., Potzel, S., Predebon, I., Preynas, M., Primc, G., Pucella, Gianluca, Puiatti, M.E., Pütterich, T., Rack, M., Ramogida, G., Rapson, C., Rasmussen, Jens Juul, Rasmussen, Jesper, Rattá, G.A., Ratynskaia, S., Ravera, G., Réfy, D., Reich, M., Reimerdes, H., Reimold, F., Reinke, M., Reiser, D., Resnik, M., Reux, C., Ripamonti, D., Rittich, D., Riva, G., Rodriguez-Ramos, M., Rohde, V., Rosato, J., Ryter, F., Saarelma, S., Sabot, R., Saint-Laurent, F., Salewski, Mirko, Salmi, A., Samaddar, D., Sanchis-Sanchez, L., Santos, J., Sauter, O., Scannell, R., Scheffer, M., Schneider, M., Schneider, B., Schneider, P., Schneller, M., Schrittwieser, R., Schubert, M., Schweinzer, J., Seidl, J., Sertoli, M., Šesnić, S., Shabbir, A., Shalpegin, A., Shanahan, B., Sharapov, S., Sheikh, U., Sias, G., Sieglin, B., Silva, C., Silva, A., Silva Fuglister, M., Simpson, James J., Snicker, A., Sommariva, C., Sozzi, C, Spagnolo, S., Spizzo, G., Spolaore, M., Stange, T., Pedersen, Morten Stejner, Stepanov, I., Stober, J., Strand, P., Šušnjara, A., Suttrop, W., Szepesi, T., Tál, B., Tala, T., Tamain, P., Tardini, G., Tardocchi, M., Teplukhina, A., Terranova, D., Testa, D., Theiler, C., Thornton, A., Tolias, P., Tophøj, Laust Emil Hjerrild, Treutterer, W., Trevisan, G.L., Tripsky, M., Tsironis, C., Tsui, C., Tudisco, O., Uccello, A., Urban, Jesper, Valisa, M., Vallejos, Paul, Valovic, M., van den Brand, H., Vanovac, B., Varoutis, S., Vartanian, S., Vega-Castillo, Jesús, Verdoolaege, G., Verhaegh, K., Vermare, L., Vianello, N., Vicente, J., Viezzer, E., Vignitchouk, L., Vijvers, W.A.J., Villone, F., Viola, B., Vlahos, L., Voitsekhovitch, I., Vondráček, P., Vu, N.M.T., Wágner, D., Walkden, N. R., Wang, N., Wauters, T., Weiland, M., Weinzettl, V., Westerhof, E., Wiesenberger, M., Willensdorfer, M., Wischmeier, M., Wodniak, I., Wolfrum, E., Yadykin, D., Zagorski, R., Zammuto, I., Zanca, P., Zaplotnik, R., Zestanakis, P., Zhang, W., Zoletnik, S., and Zuin, Matteo

Abstract

Integrating the plasma core performance with an edge and scrape-off layer (SOL) that leads to tolerable heat and particle loads on the wall is a major challenge. The new European medium size tokamak task force (EU-MST) coordinates research on ASDEX Upgrade (AUG), MAST and TCV. This multi-machine approach within EU-MST, covering a wide parameter range, is instrumental to progress in the field, as ITER and DEMO core/pedestal and SOL parameters are not achievable simultaneously in present day devices. A two prong approach is adopted. On the one hand, scenarios with tolerable transient heat and particle loads, including active edge localised mode (ELM) control are developed. On the other hand, divertor solutions including advanced magnetic configurations are studied. Considerable progress has been made on both approaches, in particular in the fields of: ELM control with resonant magnetic perturbations (RMP), small ELM regimes, detachment onset and control, as well as filamentary scrape-off-layer transport. For example full ELM suppression has now been achieved on AUG at low collisionality with n = 2 RMP maintaining good confinement HH(98,y2)≈0.95 Advances have been made with respect to detachment onset and control. Studies in advanced divertor configurations (Snowflake, Super-X and X-point target divertor) shed new light on SOL physics. Cross field filamentary transport has been characterised in a wide parameter regime on AUG, MAST and TCV progressing the theoretical and experimental understanding crucial for predicting first wall loads in ITER and DEMO. Conditions in the SOL also play a crucial role for ELM stability and access to small ELM regimes.

Published
2017

31. Annealing-induced reduction in nanoscale heterogeneity of thermally evaporated amorphous [As.sub.2][S.sub.3] films

Author

Liu, A.C.Y., Xidong Chen, Choi, D.-Y., and Luther-Davies, B.

Subjects
Annealing -- Usage, Arsenic -- Thermal properties, Arsenic -- Mechanical properties, Coating processes -- Analysis, Transmission electron microscopes -- Usage, Physics
Abstract

The morphology and structural order of thermally deposited and annealed amorphous [As.sub.2][S.sub.3] films are examined by using high resolution transmission electron microscopy. The measurements have shown that this chemical short-range ordering is associated with the dissolution of the energetically unfavorable larger correlated structures that has contributed to the inhomogeneity of the As-deposited film.

Published
2008

33. Highly manufacturable 7nm FinFET technology featuring EUV lithography for low power and high performance applications

Author

Ha, Daewon, primary, Yang, C., additional, Lee, J., additional, Lee, S., additional, Lee, S. H., additional, Seo, K.-I., additional, Oh, H. S., additional, Hwang, E. C., additional, Do, S. W., additional, Park, S. C., additional, Sun, M.-C., additional, Kim, D. H., additional, Lee, J. H., additional, Kang, M. I., additional, Ha, S.-S., additional, Choi, D. Y., additional, Jun, H., additional, Shin, H. J., additional, Kim, Y. J., additional, Moon, C. W., additional, Cho, Y. W., additional, Park, S. H., additional, Son, Y., additional, Park, J. Y., additional, Lee, B. C., additional, Kim, C., additional, Oh, Y. M., additional, Park, J. S., additional, Kim, S. S., additional, Kim, M. C., additional, Hwang, K. H., additional, Nam, S. W., additional, Maeda, S., additional, Kim, D.-W., additional, Lee, J.-H., additional, Liang, M. S., additional, and Jung, E. S., additional

Published
2017
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34. Nonlinear anisotropy in silicon nanoparticle oligomers

Author

Kroychuk, M. K., primary, Melik-Gaykazyan, E. V., additional, Shorokhov, A. S., additional, Choi, D.-Y., additional, Zubyuk, V. V., additional, Dolgova, T. V., additional, Shcherbakov, M. R., additional, Neshev, D. N., additional, Fedyanin, A. A., additional, and Kivshar, Y. S., additional

Published
2017
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35. Trans-Reflective Color Filters Based on a Phase Compensated Etalon Enabling Adjustable Color Saturation

Author

Park, C-S, Shrestha, VR, Lee, S-S, Choi, D-Y, Park, C-S, Shrestha, VR, Lee, S-S, and Choi, D-Y

Abstract

Trans-reflective color filters, which take advantage of a phase compensated etalon (silver-titania-silver-titania) based nano-resonator, have been demonstrated to feature a variable spectral bandwidth at a constant resonant wavelength. Such adjustment of the bandwidth is presumed to translate into flexible control of the color saturation for the transmissive and reflective output colors produced by the filters. The thickness of the metallic mirror is primarily altered to tailor the bandwidth, which however entails a phase shift associated with the etalon. As a result, the resonant wavelength is inevitably displaced. In order to mitigate this issue, we attempted to compensate for the induced phase shift by introducing a dielectric functional layer on top of the etalon. The phase compensation mediated by the functional layer was meticulously investigated in terms of the thickness of the metallic mirror, from the perspective of the resonance condition. The proposed color filters were capable of providing additive colors of blue, green, and red for the transmission mode while exhibiting subtractive colors of yellow, magenta, and cyan for the reflection mode. The corresponding color saturation was estimated to be efficiently adjusted both in transmission and reflection.

Published
2016

36. Active temporal multiplexing of indistinguishable heralded single photons

Author

Xiong, C, Zhang, X, Liu, Z, Collins, MJ, Mahendra, A, Helt, LG, Steel, MJ, Choi, D-Y, Chae, CJ, Leong, PHW, Eggleton, BJ, Xiong, C, Zhang, X, Liu, Z, Collins, MJ, Mahendra, A, Helt, LG, Steel, MJ, Choi, D-Y, Chae, CJ, Leong, PHW, and Eggleton, BJ

Abstract

It is a fundamental challenge in quantum optics to deterministically generate indistinguishable single photons through non-deterministic nonlinear optical processes, due to the intrinsic coupling of single- and multi-photon-generation probabilities in these processes. Actively multiplexing photons generated in many temporal modes can decouple these probabilities, but key issues are to minimize resource requirements to allow scalability, and to ensure indistinguishability of the generated photons. Here we demonstrate the multiplexing of photons from four temporal modes solely using fibre-integrated optics and off-the-shelf electronic components. We show a 100% enhancement to the single-photon output probability without introducing additional multi-photon noise. Photon indistinguishability is confirmed by a fourfold Hong-Ou-Mandel quantum interference with a 91 ± 16% visibility after subtracting multi-photon noise due to high pump power. Our demonstration paves the way for scalable multiplexing of many non-deterministic photon sources to a single near-deterministic source, which will be of benefit to future quantum photonic technologies.

Published
2016

41. Polarization-tuned Dynamic Color Filters Incorporating a Dielectric-loaded Aluminum Nanowire Array

Author

Shrestha, VR, Lee, S-S, Kim, E-S, Choi, D-Y, Shrestha, VR, Lee, S-S, Kim, E-S, and Choi, D-Y

Abstract

Nanostructured spectral filters enabling dynamic color-tuning are saliently attractive for implementing ultra-compact color displays and imaging devices. Realization of polarization-induced dynamic color-tuning via one-dimensional periodic nanostructures is highly challenging due to the absence of plasmonic resonances for transverse-electric polarization. Here we demonstrate highly efficient dynamic subtractive color filters incorporating a dielectric-loaded aluminum nanowire array, providing a continuum of customized color according to the incident polarization. Dynamic color filtering was realized relying on selective suppression in transmission spectra via plasmonic resonance at a metal-dielectric interface and guided-mode resonance for a metal-clad dielectric waveguide, each occurring at their characteristic wavelengths for transverse-magnetic and electric polarizations, respectively. A broad palette of colors, including cyan, magenta, and yellow, has been attained with high transmission beyond 80%, by tailoring the period of the nanowire array and the incident polarization. Thanks to low cost, high durability, and mass producibility of the aluminum adopted for the proposed devices, they are anticipated to be diversely applied to color displays, holographic imaging, information encoding, and anti-counterfeiting.

Published
2015

42. Compact and reconfigurable silicon nitride time-bin entanglement circuit

Author

Xiong, C, Zhang, X, Mahendra, A, He, J, Choi, D-Y, Chae, CJ, Marpaung, D, Leinse, A, Heideman, RG, Hoekman, M, Roeloffzen, CGH, Oldenbeuving, RM, van Dijk, PWL, Taddei, C, Leong, PHW, Eggleton, BJ, Xiong, C, Zhang, X, Mahendra, A, He, J, Choi, D-Y, Chae, CJ, Marpaung, D, Leinse, A, Heideman, RG, Hoekman, M, Roeloffzen, CGH, Oldenbeuving, RM, van Dijk, PWL, Taddei, C, Leong, PHW, and Eggleton, BJ

Published
2015

43. Omnidirectional color filters capitalizing on a nano-resonator of Ag-TiO2-Ag integrated with a phase compensating dielectric overlay

Author

Park, C-S, Shrestha, VR, Lee, S-S, Kim, E-S, Choi, D-Y, Park, C-S, Shrestha, VR, Lee, S-S, Kim, E-S, and Choi, D-Y

Abstract

We present a highly efficient omnidirectional color filter that takes advantage of an Ag-TiO2-Ag nano-resonator integrated with a phase-compensating TiO2 overlay. The dielectric overlay substantially improves the angular sensitivity by appropriately compensating for the phase pertaining to the structure and suppresses unwanted optical reflection so as to elevate the transmission efficiency. The filter is thoroughly designed, and it is analyzed in terms of its reflection, optical admittance, and phase shift, thereby highlighting the origin of the omnidirectional resonance leading to angle-invariant characteristics. The polarization dependence of the filter is explored, specifically with respect to the incident angle, by performing experiments as well as by providing the relevant theoretical explanation. We could succeed in demonstrating the omnidirectional resonance for the incident angles ranging to up to 70°, over which the center wavelength is shifted by below 3.5% and the peak transmission efficiency is slightly degraded from 69%. The proposed filters incorporate a simple multi-layered structure and are expected to be utilized as tri-color pixels for applications that include image sensors and display devices. These devices are expected to allow good scalability, not requiring complex lithographic processes.

Published
2015

44. Photonic-Chip-Based Ultrafast Waveform Analysis and Optical Performance

Author

Vo, T.d., Schröder, J., Corcoran, B., Van Erps, Jurgen, Madden, S., Choi, D- Y., Bulla, D.a.p., Luther-Davies, B., Pelusi, M.d., Eggleton, B., and Brussels Photonics Team

Subjects
HIGHLY NONLINEAR FIBERS, MANAGED SOLITON SYSTEM, WAVELENGTH CONVERSION, OTDM SIGNAL, RF SPECTRUM ANALYSIS, SEMICONDUCTOR-LASER AMPLIFIERS, Physics::Optics, TIMING JITTER MEASUREMENTS, TERAHERTZ BANDWIDTH, IN-BAND OSNR, CHROMATIC DISPERSION
Abstract

We review waveform analysis and optical performance monitoring of ultrabroadband signals using a photonic-chip-based radio-frequency spectrum analyzer. This approach offers the potential for fast integrated monitoring and characterization of signals with bandwidths beyond 1 THz.

Published
2012

46. Compact and reconfigurable silicon nitride time-bin entanglement circuit

Author

Xiong, C., primary, Zhang, X., additional, Mahendra, A., additional, He, J., additional, Choi, D.-Y., additional, Chae, C. J., additional, Marpaung, D., additional, Leinse, A., additional, Heideman, R. G., additional, Hoekman, M., additional, Roeloffzen, C. G. H., additional, Oldenbeuving, R. M., additional, van Dijk, P. W. L., additional, Taddei, C., additional, Leong, P. H. W., additional, and Eggleton, B. J., additional

Published
2015
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50. Automatic dispersion compensation for 1.28Tb/s OTDM signal transmission using photonic-chip-based dispersion monitoring

Author

Van Erps, Jurgen, Schröder, J., Vo, T.d., Pelusi, M.d., Madden, S., Choi, D- Y., Bulla, D.a., Luther-Davies, B., Eggleton, B., and Applied Physics and Photonics

Subjects
OPTICAL SIGNALS, FIBER, CHROMATIC DISPERSION, SPECTRUM ANALYZER
Abstract

We present automatic dispersion control of 1.28 Tb/s optical time domain multiplexed signals. The dispersion is monitored by measuring the power of the 1.28 THz tone of the RF spectrum using a photonic-chip-based radio-frequency spectrum analyzer (PC-RFSA) and the dispersion compensation is realized by means of a spectral pulse shaper, via computer-controlled feedback from the PC-RFSA.

Published
2010

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