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Numerical modeling of THz photoconductive antennas in a Discontinuous Galerkin Time-Domain framework
Duration: 6 months
Research and development engineer (fixed-term)
Exascale enabled finite element solvers for nanophotonics
Duration: 16 months
Research and development engineer (fixed-term)
High order finite element solvers for the design of nanophotonic devices
Duration: 12 months
News - February 2019
Paper entitled "Optimization and uncertainty quantification of gradient index
metasurfaces" by N. Schmitt, N. Georg, G. Brière, D. Loukrezis, S. Héron, S. Lanteri, C. Klitis, M. Sorel, U. Römer, H. De Gersem, S. Vézian and P. Genevet
Opt. Mat. Express., Vol. 9, No. 2, pp. 892-910 (2019)
In this multidisciplinary work involving researchers in physics and applied mathematics, we present a computational methodology to optimize metasurface designs. We complement this computational methodology by quantifying the impact of fabrication uncertainties on the experimentally characterized components.
(a) Illustrative schematic of the angular deflection property of a phase gradient metasurface.
(b)-(c) The metasurface-based device works essentially as conventional echelette blazed grating, by replacing the periodic echelette with a subwavelength array of nanoridges.
(d) Typical broadband response of the transmission efficiency for an optimized metasurface obtained using two different electromagnetic simulation solvers, the Discontinuous Galerkin Time-Domain solver (DGTD) solver and the Rigorous Coupled Wave Analysis (RCWA) solver in orange dashed.
News - November 2018
Paper entitled "The Multiscale Hybrid-Mixed method for the Maxwell equations in heterogeneous media" by S. Lanteri, D. Paredes, C. Scheid and F. Valentin
SIAM J. Multiscale Model. Simul., Vol. 16, No. 4, pp.1648–1683 (2018)
Simulating wave propagation in three-dimensional highly heterogeneous media or heterogeneous media with complex interfaces remains a challenging task. In many modern applications, this phenomena is associated with high frequency responses when compared to the size of the domain. Classical numerical methods, like finite difference or finite element methods, must use a very fine mesh to obtain high quality solutions, which results in huge computational resource requirements. The Multiscale Hybrid-Mixed (MHM) method implements the “divide-and-conquer” philosophy to obtain accurate solutions on coarse meshes. Based on a classical hybridization procedure, the MHM method yields a staggered algorithm , which is organized around two main ingredients: (1) a set of multiscale basis functions, which are constructed as the solution of local problems defined in each macro cell of the coarse mesh; (2) a global problem defined on the skeleton of the coarse mesh that gives rise to a classical finite element formulation leveraging the multiscale basis functions. In the context of electromagnetic wave propagation modelled by the system of time-domain Maxwell equations, the local problems are solved using a classical DGTD method.
Nanowaveguide problem: contour lines of
the amplitude of the electric field. Left: DGTD method with 5898,824 Dof - Middle: DGTD methid withg 4,608 DoF - Right: MHM-DGTD method with 9,216 DoF
News - October 2018
Welcome to Théophile Chaumont-Frelet who has been awarded a Junior research scientist position in the team!
Kick-off of the EPEEC (European joint Effort toward a Highly Productive Programming Environment for Heterogeneous Exascale Computing) H2020 project
Welcome to Mahmoud Elsawy who joined the team as a postodtcoral fellow!
Paper entitled "Simulation of three-dimensional nanoscale light interaction with spatially dispersive metals using a high order curvilinear DGTD method" by N. Schmitt, C. Scheid, J. Viquerat and S. Lanteri
J. Comput. Phys., Vol. 373, pp. 210–229 (2018)
News - September 2018
Congratulations to Nikolaï Schmitt who defended his doctoral thesis on September 27!
Paper entitled "Fitting experimental dispersion data with a simulated annealing method for nano-optics applications" by J. Viquerat
J. of Nanophotonics, Vol. 12, No. 3, 036014 (2018)
News - March 2018
Kick-off meeting of the Math-Amsud PHOTOM - Photovoltaic Solar Devices
in Multiscale Computational Simulations - project
March 13-15, LNCC, Petrópolis, Brazil
New high order Hybridized Discontinuous Solver (HDG) for frequency-domain plasmonics in 3D - Work done in the context of the postdoctoral project of Mostafa Javadzadeh Moghtader
Scattering of a plane wave by a 50 nm gold nanosphere: magnitude of E field at frequencies 1070 THz (left), 1185 THz (middle) and 1300 THz (right)
Scattering of a plane wave by a 50 nm gold nanosphere: scattering (left) and absorption (right) cross sections for calculations based on a HDG method with quadratic interpolation of the EM field components
News - February 2018
Congratulations to Fréderic Valentin who has been awarded an Inria International Chair for the period 2018-2022! The research project that he will lead during this period aims at devising innovative multiscale numerical algorithms for the simulation of wave-matter interaction at the nanoscale. This topic is also at the heart of the Math-Amsud PHOTOM - Photovoltaic Solar Devices
in Multiscale Computational Simulations - project that has started in Januray 2018 for a duration of 2 years, and which involves researchers from Brazil, Chile and France.
Papers on reduced-order modeling based on Proper Orthogonal Decomposition for time-domain electromagnetics in the context of a collaborative work with researchers from UESTC, Chengdu, China.
K. Li, T.-Z. Huang, L. Li and S. Lanteri
A reduced-order DG formulation based on POD method for the time-domain Maxwell’s equations in dispersive media
J. Comput. Appl. Math., Vol. 336, pp. 249-266 (2018)
K. Li, T.-Z. Huang, L. Li, S. Lanteri, L. Xu and B. Li
A reduced-order discontinuous Galerkin method based on POD for electromagnetic simulation
IEEE Trans. Ant. Propag., Vol. 66, No. 1, pp. 242-254 (2018)
News - May 2017
High order DGTD method based on exponential time integrators for modeling
3D transient multiscale electromagnetic problems
More details - Work done in the context of the PhD project of Hao Wang
H. Wang, L. Xu, B. Li, S. Descombes and S. Lanteri
A new family of exponential-based high order DGTD methods for modelling 3D transient multiscale electromagnetic problems
IEEE Trans. Ant. Propag., Vol. 65, No. 11, pp. 5960-5974 (2017)
News - February 2017
Paper entitled "Analysis of a generalized dispersive model coupled to a DGTD method with application to nanophotonics" by S. Lanteri, C. Scheid and J. Viquerat
SIAM J. Sci. Comp., Vol. 39, No. 3, pp. A831–A859 (2017)
Simulation of light trapping in thin-film solar cells with textured layers
More details - Work done in the context of the PhD project of Alexis Gobé