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Martins FLB, Rodrigues JPT, Nascimento JC. All-optical digital multiplexer/demultiplexer in a linear three-core fiber device. APPLIED OPTICS 2022; 61:8515-8521. [PMID: 36256168 DOI: 10.1364/ao.470630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 09/09/2022] [Indexed: 06/16/2023]
Abstract
Digital multiplexers/demultiplexers (MUX/DEMUXes) are essential for computing, data transmission, and data processing. However, research on all-optical digital MUX/DEMUXes is scarce and generally proposes single-function nonlinear devices. This work presents the numerical acquisition of all-optical digital MUX/DEMUXes using a linear three-core fiber device. Our device, called the interchanging-cores planar three-core fiber coupler, is propagated by low-powered amplitude modulated pulses, can operate with pulses of any wavelength, and can be made using any fiber technology. This result is further evidence of the possibility of obtaining logical processing, even nonlinear logical processing, using fiber-only design.
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Rodrigues JPT, Martins FLB, Júnior VPP, Nascimento JC. Linear multi-functional logic gate in a three-core photonic crystal fiber. APPLIED OPTICS 2021; 60:9225-9230. [PMID: 34624008 DOI: 10.1364/ao.440191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Accepted: 09/14/2021] [Indexed: 06/13/2023]
Abstract
The growth of transmission rates in optical fibers can increase the demand for devices that perform network node processing. Usually, such devices achieve complex optical signal processing through high non-linearity effects and optoelectronic devices. In this work, we present the numerical acquisition of a configurable multi-function logic gate in which the OR and AND gates can be enabled based on the logic values entered in a selector. Our device consists of a single piece of three-core PCF, with linear pulse propagation, and without the need for any other mechanisms. This result presents evidence that information processing within functional fibers is possible and might be achieved using only fiber design.
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3
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Design and Dispersion Control of Microstructured Multicore Tellurite Glass Fibers with In-Phase and Out-of-Phase Supermodes. PHOTONICS 2021. [DOI: 10.3390/photonics8040113] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
High nonlinearity and transparency in the 1–5 μm spectral range make tellurite glass fibers highly interesting for the development of nonlinear optical devices. For nonlinear optical fibers, group velocity dispersion that can be controlled by microstructuring is also of great importance. In this work, we present a comprehensive numerical analysis of dispersion and nonlinear properties of microstructured two-, four-, six-, and eight-core tellurite glass fibers for in-phase and out-of-phase supermodes and compare them with the results for one-core fibers in the near- and mid-infrared ranges. Out-of-phase supermodes in tellurite multicore fibers are studied for the first time, to the best of our knowledge. The dispersion curves for in-phase and out-of-phase supermodes are shifted from the dispersion curve for one-core fiber in opposite directions; the effect is stronger for large coupling between the fields in individual cores. The zero dispersion wavelengths of in-phase and out-of-phase supermodes shift to opposite sides with respect to the zero-dispersion wavelength of a one-core fiber. For out-of-phase supermodes, the dispersion can be anomalous even at 1.55 μm, corresponding to the operating wavelength of Er-doped fiber lasers.
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4
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Li H, Peng X, Shi Z. Vector solitons in nonlocal optical media with pseudo spin-orbit-coupling. Phys Rev E 2021; 103:022205. [PMID: 33736013 DOI: 10.1103/physreve.103.022205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 01/15/2021] [Indexed: 11/07/2022]
Abstract
We numerically investigate the existence and stability of nonlocal vector solitons with pseudo spin-orbit-coupling (SOC). The pseudo SOC is realized by a framework based on the spatial-domain copropagation of two beams with mutually orthogonal polarizations and opposite transverse components of the carrier wave vectors in nonlocal optical media. The numerical results show that there are two kinds of solutions for vector solitons, one is central symmetric, and the other is noncentral symmetric. The solitons may exist below a certain threshold value of the effective SOC strength in the system.
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Affiliation(s)
- Huagang Li
- School of Photoelectric Engineering, Guangdong Polytechnic Normal University, Guangzhou 510665, China
| | - Xi Peng
- School of Photoelectric Engineering, Guangdong Polytechnic Normal University, Guangzhou 510665, China
| | - Zhiwei Shi
- School of Electro-mechanical Engineering, Guangdong University of Technology, Guangzhou 510006, China
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Nguyen VH, The Tai LX, Bugar I, Longobucco M, Buczyński R, Malomed BA, Trippenbach M. Reversible ultrafast soliton switching in dual-core highly nonlinear optical fibers. OPTICS LETTERS 2020; 45:5221-5224. [PMID: 32932495 DOI: 10.1364/ol.404039] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 08/19/2020] [Indexed: 06/11/2023]
Abstract
We experimentally investigate a nonlinear switching mechanism in a dual-core highly nonlinear optical fiber. We focus the input stream of femtosecond pulses on one core only, to identify transitions between inter-core oscillations, self-trapping in the cross core, and self-trapping of the pulse in the straight core. A model based on the system of coupled nonlinear Schrödinger equations provides surprisingly good agreement with the experimental findings.
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6
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Abstract
We consider possibilities to control dynamics of solitons of two types, maintained by the combination of cubic attraction and spin-orbit coupling (SOC) in a two-component system, namely, semi-dipoles (SDs) and mixed modes (MMs), by making the relative strength of the cross-attraction, γ , a function of time periodically oscillating around the critical value, γ = 1 , which is an SD/MM stability boundary in the static system. The structure of SDs is represented by the combination of a fundamental soliton in one component and localized dipole mode in the other, while MMs combine fundamental and dipole terms in each component. Systematic numerical analysis reveals a finite bistability region for the SDs and MMs around γ = 1 , which does not exist in the absence of the periodic temporal modulation (“management”), as well as emergence of specific instability troughs and stability tongues for the solitons of both types, which may be explained as manifestations of resonances between the time-periodic modulation and intrinsic modes of the solitons. The system can be implemented in Bose-Einstein condensates (BECs), and emulated in nonlinear optical waveguides.
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Wang C, Li J. Saturable absorber based on the CS 2-filled dual-core fiber coupler. OPTICS EXPRESS 2018; 26:22144-22159. [PMID: 30130912 DOI: 10.1364/oe.26.022144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Accepted: 08/03/2018] [Indexed: 06/08/2023]
Abstract
It is demonstrated by numerical simulations that the CS2-filled dual-core fiber coupler with appropriate parameters can provide single-mode operation, normal dispersions, low loss and high nonlinearities in 1550-nm and 2000-nm wavelength windows, which can contribute to a saturable absorber (SA) with short fiber length and low power needed for nonlinearity-induced saturation. The effects of stimulated Raman scattering (SRS) play a key role in the process of nonlinearity-induced saturation. The numerical results indicate that the SAs can be employed in the mode-locking fiber lasers with self-similar (SS) or dissipative soliton (DS) operations.
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8
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Symmetry Breakings in Dual-Core Systems with Double-Spot Localization of Nonlinearity. Symmetry (Basel) 2018. [DOI: 10.3390/sym10050156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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9
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Modulational Instability in Linearly Coupled Asymmetric Dual-Core Fibers. APPLIED SCIENCES-BASEL 2017. [DOI: 10.3390/app7070645] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Zezyulin DA, Kartashov YV, Konotop VV. CPT-symmetric coupler with intermodal dispersion. OPTICS LETTERS 2017; 42:1273-1276. [PMID: 28362746 DOI: 10.1364/ol.42.001273] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A dual-core waveguide with balanced gain and loss in different arms and with intermodal coupling is considered. The system is not invariant under the conventional PT symmetry, but obeys CPT symmetry where an additional spatial inversion C corresponds to swapping the coupler arms. We show that second-order dispersion of coupling allows for unbroken CPT symmetry and supports propagation of stable vector solitons along the coupler. Small-amplitude solitons are found in explicit form. The combined effect of gain-and-loss and dispersive coupling results in several interesting features which include a separation between the components in different arms, nontrivial dependence of stability of a soliton on its velocity, and the existence of more complex stationary two-hump solutions. Unusual decay dynamics of unstable solitons are also discussed.
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11
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A PT -Symmetric Dual-Core System with the Sine-Gordon Nonlinearity and Derivative Coupling. Symmetry (Basel) 2016. [DOI: 10.3390/sym8060039] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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12
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Parto M, Eftekhar MA, Miri MA, Amezcua-Correa R, Li G, Christodoulides DN. Systematic approach for designing zero-DGD coupled multi-core optical fibers. OPTICS LETTERS 2016; 41:1917-1920. [PMID: 27128038 DOI: 10.1364/ol.41.001917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
An analytical method is presented for designing N-coupled multi-core fibers with zero differential group delay. This approach effectively reduces the problem to a system of N-1 algebraic equations involving the associated coupling coefficients and propagation constants, as obtained from coupled mode theory. Once the parameters of one of the cores are specified, the roots of the resulting N-1 equations can be used to determine the characteristics of the remaining waveguide elements. Using this technique, a number of pertinent geometrical configurations are investigated to minimize intermodal dispersion.
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Zhang YC, Zhou ZW, Malomed BA, Pu H. Stable Solitons in Three Dimensional Free Space without the Ground State: Self-Trapped Bose-Einstein Condensates with Spin-Orbit Coupling. PHYSICAL REVIEW LETTERS 2015; 115:253902. [PMID: 26722921 DOI: 10.1103/physrevlett.115.253902] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Indexed: 06/05/2023]
Abstract
By means of variational methods and systematic numerical analysis, we demonstrate the existence of metastable solitons in three dimensional (3D) free space, in the context of binary atomic condensates combining contact self-attraction and spin-orbit coupling, which can be engineered by available experimental techniques. Depending on the relative strength of the intra- and intercomponent attraction, the stable solitons feature a semivortex or mixed-mode structure. In spite of the fact that the local cubic self-attraction gives rise to the supercritical collapse in 3D, and hence the setting produces no true ground state, the solitons are stable against small perturbations, motion, and collisions.
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Affiliation(s)
- Yong-Chang Zhang
- Key Laboratory of Quantum Information, and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Zheng-Wei Zhou
- Key Laboratory of Quantum Information, and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Boris A Malomed
- Department of Physical Electronics, School of Electrical Engineering, Faculty of Engineering, Tel Aviv University, 69978 Tel Aviv, Israel
| | - Han Pu
- Department of Physics and Astronomy, and Rice Center for Quantum Materials, Rice University, Houston, Texas 77005, USA
- Center for Cold Atom Physics, Chinese Academy of Sciences, Wuhan 430071, China
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Solntsev AS, Sukhorukov AA. Modulated coupled nanowires for ultrashort pulses. OPTICS LETTERS 2015; 40:4078-4081. [PMID: 26368716 DOI: 10.1364/ol.40.004078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We predict analytically and confirm with numerical simulations that intermode dispersion in nanowire waveguide arrays can be tailored through periodic waveguide bending, facilitating flexible spatiotemporal reshaping without breakup of femtosecond pulses. This approach allows simultaneous and independent control of temporal dispersion and spatial diffraction that are often strongly connected in nanophotonic structures.
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Wu Y, Chiang KS. Compact three-core fibers with ultra-low differential group delays for broadband mode-division multiplexing. OPTICS EXPRESS 2015; 23:20867-20875. [PMID: 26367940 DOI: 10.1364/oe.23.020867] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
An approximate explicit condition for the achievement of zero differential group delay (DGD) in a homogeneous multicore fiber (MCF) is presented and verified numerically for a step-index three-core fiber. This condition is explored for the study of compact three-core fibers with low DGDs. To achieve an ultra-low DGD in the C-band, a three-core fiber with a central refractive-index dip in each core is proposed and analyzed in detail. A specific design with three touching cores and a core-cladding index difference of 0.3% yields a maximum DGD smaller than 3.2 ps/km in the C-band. The fiber is suitable for broadband mode-division multiplexing applications and the design approach could be applied to MCFs with more cores.
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Kartashov YV, Malomed BA, Konotop VV, Lobanov VE, Torner L. Stabilization of spatiotemporal solitons in Kerr media by dispersive coupling. OPTICS LETTERS 2015; 40:1045-1048. [PMID: 25768178 DOI: 10.1364/ol.40.001045] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We introduce a mechanism to stabilize spatiotemporal solitons in Kerr nonlinear media, based on the dispersion of linear coupling between the field components forming the soliton states. Specifically, we consider solitons in a two-core guiding structure with inter-core coupling dispersion (CD). We show that CD profoundly affects properties of the solitons, causing the complete stabilization of the otherwise highly unstable spatiotemporal solitons in Kerr media with focusing nonlinearity. We also find that the presence of CD stimulates the formation of bound states, which, however, are unstable.
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17
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Malomed BA, Shnir Y, Zhilin G. Spontaneous symmetry breaking in dual-core baby-Skyrmion systems. Int J Clin Exp Med 2014. [DOI: 10.1103/physrevd.89.085021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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18
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Espinosa-Cerón A, Malomed BA, Fujioka J, Rodríguez RF. Symmetry breaking in linearly coupled Korteweg-de Vries systems. CHAOS (WOODBURY, N.Y.) 2012; 22:033145. [PMID: 23020484 DOI: 10.1063/1.4752244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We consider solitons in a system of linearly coupled Korteweg-de Vries (KdV) equations, which model two-layer settings in various physical media. We demonstrate that traveling symmetric solitons with identical components are stable at velocities lower than a certain threshold value. Above the threshold, which is found exactly, the symmetric modes are unstable against spontaneous symmetry breaking, which gives rise to stable asymmetric solitons. The shape of the asymmetric solitons is found by means of a variational approximation and in the numerical form. Simulations of the evolution of an unstable symmetric soliton sometimes produce its breakup into two different asymmetric modes. Collisions between moving stable solitons, symmetric and asymmetric ones, are studied numerically, featuring noteworthy features. In particular, collisions between asymmetric solitons with identical polarities are always elastic, while in the case of opposite polarities the collision leads to a switch of the polarities of both solitons. Three-soliton collisions are studied too, featuring quite complex interaction scenarios.
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Affiliation(s)
- A Espinosa-Cerón
- Departamento de Física-Química, Instituto de Física, Universidad Nacional Autónoma de México, México, D.F., C.P. 04510, Mexico
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Driben R, Malomed BA. Stability of solitons in parity-time-symmetric couplers. OPTICS LETTERS 2011; 36:4323-4325. [PMID: 22089551 DOI: 10.1364/ol.36.004323] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Families of analytical solutions are found for symmetric and antisymmetric solitons in a dual-core system with Kerr nonlinearity and parity-time (PT)-balanced gain and loss. The crucial issue is stability of the solitons. A stability region is obtained in an analytical form, and verified by simulations, for the PT-symmetric solitons. For the antisymmetric ones, the stability border is found in a numerical form. Moving solitons of both types collide elastically. The two soliton species merge into one in the "supersymmetric" case, with equal coefficients of gain, loss, and intercore coupling. These solitons feature a subexponential instability, which may be suppressed by periodic switching ("management").
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Affiliation(s)
- Rodislav Driben
- Jerusalem College of Engineering-Ramat Beit HaKerem, Jerusalem, Israel.
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20
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Liu M, Chiang KS. Pulse propagation in a decoupled two-core fiber. OPTICS EXPRESS 2010; 18:21261-21268. [PMID: 20941022 DOI: 10.1364/oe.18.021261] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
It is known that a decoupled two-core fiber can prevent monochromatic light at a specific wavelength (the decoupling wavelength) launched into one core from coupling to the other core. In this paper, we show that a pulse at the decoupling wavelength launched into one core of such a fiber inevitably splits into two pairs of pulses propagating in the two cores along the fiber. The minimum distance required for pulse splitting to be visible is inversely proportional to the coupling-coefficient dispersion in the fiber and linearly proportional to the pulse width. It would take only several centimeters of a recently demonstrated decoupled two-core photonic-bandgap fiber to observe the pulse-splitting effect with a 100-fs pulse. We also study the effects of self-phase modulation on the pulse propagation dynamics in a decoupled two-core fiber in both the normal and anomalous dispersion regimes.
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Affiliation(s)
- M Liu
- College of Communication Engineering, Chongqing University, Chongqing, China.
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Cuesta-Soto F, García-Baños B, Martí J. Compensating intermodal dispersion in photonic crystal directional couplers. OPTICS LETTERS 2005; 30:3156-8. [PMID: 16342707 DOI: 10.1364/ol.30.003156] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Intermodal dispersion between the supermodes of a directional coupler may induce undesirable pulse breakup in a sufficiently large device. When this happens the device will no longer exchange power between its arms, and the extinction ratio is completely canceled. It is shown that, by carefully designing the coupling area of the directional coupler, one may compensate for intermodal dispersion. The compensating device should accomplish three basic requirements: inverse intermodal dispersion, balanced coupling of each supermode, and maximum power transfer while preserving the sign of the slope of the coupling coefficient with frequency for multiplexing-demultiplexing applications. This structure is designed and optimized with a genetic algorithm.
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Affiliation(s)
- Francisco Cuesta-Soto
- Valencia Nanophotonics Technology Center, Universidad Politécnica de Valencia, Spain.
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