Armin Lechleiter Centre de Mathématiques Appliquées Equipe DeFI Ecole Polytechnique Route de Saclay 91128 Palaiseau Cedex France Phone: +33 1 69 33 46 35 Fax: +33 1 69 33 59 46 Email: alechle(at)cmap.polytechnique.fr

Welcome to my home page!

I'm a researcher (chargé de recherche) in applied mathematics working in the DeFI team. This is a joint research group of INRIA Saclay Ile de France and Ecole Polytechnique. The group is located in the applied math department Centre de Mathématiques Appliquées of Ecole Polytechnique. Our group is interested, broadly speaking, in inverse problems and shape optimization. See our website for more details

Publications

• A regularization technique for the factorization method, Inverse Problems 22 (2006) 1605-1625, pdf

• with A. Rieder: Newton regularizations for impedance tomography: a numerical study, Inverse Problems 22 (2006) 1967-1987, pdf (grey-scale), pdf (color). Chosen as IOPSelect.

• with Tilo Arens and Drossos Gintides: Variational formulations for scattering in a 3-dimensional acoustic waveguide, Math. Meth. Appl. Sci. 31 (2008) 821-847, pdf

• with Nuutti Hyvönen and Harri Hakula: The factorization method applied to the complete electrode model of impedance tomography, SIAM J. Appl. Math. 68 (2008) 1097-1121, pdf

• with Andreas Rieder: Newton regularizations for impedance tomography: convergence by local injectivity, Inverse Problems 24 (2008) 065009, pdf

• with Tilo Arens: The linear sampling method revisited, J. Int. Eq. Appl. 21 (2009) 179-202 (Special issue dedicated to Rainer Kress), pdf

• The factorization method is independent of transmission eigenvalues, Inverse Problems and Imaging 3 (2009) 123-138, pdf

• with Andreas Kirsch: The operator equations of Lippmann-Schwinger type for acoustic and electromagnetic scattering problems in L^2, Applicable Analysis 88 (2009) 807-830, pdf

• with Andreas Rieder: Towards a general convergence theory for inexact Newton regularizations, Numer. Math. 114 (2010) 521-548, pdf

• with Tilo Arens and D. Russell Luke: MUSIC for extended scatterers as an instance of the Factorization method, SIAM J. Appl. Math. 70 (2009) 1283-1304, pdf

• with Sebastian Ritterbusch: A variational method for scattering from penetrable rough layers, IMA J. Appl. Math. 75 (2010) 366-391, pdf

• with Houssem Haddar: Asymptotic models for scattering problems from unbounded media with high conductivity, M2AN, 44 (2010) 1295-1317, pdf

• Imaging of Periodic Dielectrics, BIT Numerical Mathematics 50 (2010) 59-83, pdf

• with Qiang Chen, Houssem Haddar and Peter Monk: A Sampling Method for Inverse Scattering in the Time Domain, Inverse Problems 26 (2010) 085001, pdf

• with Tilo Arens and Drossos Gintides: Direct and inverse medium scattering in a 3D homogeneous planar waveguide, SIAM Journal of Applied Mathematics 71 (2011) 753-772, pdf

• Explicit characterization of the support of non-linear inclusions, accepted for Inverse Problems and Imaging, pdf

• with Dinh Liem Nguyen: Spectral volumetric integral equation methods for acoustic medium scattering in a planar homogeneous 3D waveguide, accepted for the IMA Journal of Numerical Analysis, pdf

Preprints & Technical Reports

• with Houssem Haddar: Electromagnetic wave scattering from rough penetrable layers, pdf

• with Tilo Arens, Kai Sandfort, and Susanne Schmitt: Analysing Ewald's method for the evaluation of Green's functions for periodic media, pdf

Theses

• Factorization Methods for Photonics and Rough Surfaces. Download. PhD thesis, Universität Karlsruhe (TH), 2008

• Classical and New Approaches to the Impedance Tomography Problem. Diploma thesis, Universität Karlsruhe (TH), 2005

Links

• MMNS 2010 Spring Workshop on Inverse Problems for Waves

• DeFI has a regular workgroup meeting

• My old group at University of Karlsruhe, which is, amongst others, working on inverse problems and integral equations

• The workgroup on scattering and inverse scattering at the University of Delaware

• The workgroups on inverse problems at the Institut für Numerische und Angewandte Mathematik of the University of Göttingen

• The Arbeitsgruppe Numerische Mathematik at University of Mainz, working on inverse problems with applications, e.g., in impedance tomography

• The INRIA group Corida at University of Nancy is also working on inverse problems

• The Inverse Modelling Group at University of Reading

• The Inverse Problems Research Group at Helsinki University of Technology - TKK

• The Finnish Inverse Problems Society