Mattia Walschaers

Mattia Walschaers

Research scientist (chargé de recherche)



Previous work

Mattia Walschaers got his PhD from the universities of Freiburg (Germany) and Leuven (Belgium) for a cotutelle project, supervised by Andreas Buchleitner and Mark Fannes. His work initially focused on the role of quantum effects in photosynthesis, where he developed analytically solvable toy models to better understand the role of disorder in coherent transport of photosynthetic excitons. Later on, his interest shifted to many-particle systems. First he tried to understand the highest possible current that can flow through many-fermion systems in a non-equilibrium steady state. Then the attention shifted to dynamical features of many-particle systems on transient time scales. In particular, Mattia spent a big part of the final years of his PhD project working on many-particle interference a phenomenon which induced by indistinguishability of quantum particles. This ultimately led to the development of an experimentally implementable statistical benchmark for boson sampling.
The resulting dissertation was published as a book in the Springer Theses series, and it was also one of the four nominees for the SAMOP dissertation prize of the German Physical Society.

Since September 2016, Mattia is a post-doctoral researcher in multimode quantum optics group of the Laboratoire Kastler Brossel, where his research interests shifted to continuous-variable quantum optics and quantum information. With specific interest for highly multimode systems, he mixes standard approaches in the field with tools from statistical physics. At the moment, most of his attention is devoted to understanding experimentally feasible non-Gaussian states in these systems. As such, he used techniques based on multimode correlation functions to develop a general framework to study multimode photon addition and subtraction. Between May 2018 and October 2019, Mattia was funded by a research fellowship from the German Research Foundation (DFG) to extend his stay at the LKB and further explore these topics.

Current work

In April 2019, Mattia was recruited by the CNRS and in October 2019 he started a permanent research position at the LKB. His research builds up on his post-doc work in the multimode quantum optics group, where he now explores various aspects of continuous variable quantum physics. Among current research interests: multimode non-Gaussian quantum states, quantum correlations in CV systems, quantum batteries, complex quantum networks, and applications of machine learning in quantum experiments

Selected Publications


Full Bibliography


Research Articles

  • M. Walschaers, V. Parigi, and N. Treps, Practical Framework for Conditional Non-Gaussian Quantum State PreparationPRX Quantum 1, 020305 (2020)

  • V. Cimini, M. Barbieri, N. Treps, M. Walschaers, and V. Parigi, Neural Networks for Detecting Multimode Wigner Negativity, Phys. Rev. Lett. 125, 160504 (2020)

  • D. Barral, M. Walschaers, K. Bencheikh, V. Parigi, J. A. Levenson, N. Treps, and N. Belabas, Quantum state engineering in arrays of nonlinear waveguides, Phys. Rev. A 102, 043706 (2020).
  • D. Barral, M. Walschaers, K. Bencheikh, V. Parigi, J. A. Levenson, N. Treps, and N. Belabas, Versatile Photonic Entanglement Synthesizer in the Spatial DomainPhys. Rev. Applied 14, 044025 (2020).

  • F. Flamini, M. Walschaers, N. Spagnolo, N. Wiebe, A. Buchleitner, F. Sciarrino, Validating multi-photon quantum interference with finite data, Quantum Sci. Technol.5 045005 (2020)

  • M. Walschaers and N. Treps, Remote generation of Wigner-negativity through Einstein-Podolsky-Rosen steering, Phys. Rev. Lett. 124, 150501 (2020).

  • Y.-S. Ra, A. Dufour, M. Walschaers, C. Jacquard, T. Michel, C. Fabre, N. Treps, Non-Gaussian quantum states of a multimode light field, Nat. Phys. 16, 144–147(2020).


Research articles

  • U. Chabaud, G. Roeland, M. Walschaers, F. Grosshans, V. Parigi, D. Markham, N. Treps, Certification of non-Gaussian states with operational measurements, arXiv:2011.04320

  • P. Boucher, A. Goetschy, G. Sorelli, M. Walschaers, N. Treps, Full characterization of the transmission properties of a multi-plane light converter, arXiv:2005.11982

Research Articles

  • M. Walschaers, Y.-S. Ra, N. Treps, Mode-Dependent Loss Model for Multimode Photon-Subtracted States, Phys. Rev. A 100, 023828 (2019).
  • D. S. Phillips, M. Walschaers, J. J. Renema, I. A. Walmsley, N. Treps, J. Sperling, Benchmarking of Gaussian boson sampling using two-point correlators, Phys. Rev. A 99, 023836 (2019).
Research articles
  • T. Giordani, F. Flamini, M. Pompili, N. Viggianiello, N. Spagnolo, A. Crespi, R. Osellame, N. Wiebe, M. Walschaers, A. Buchleitner, and F. Sciarrino, Experimental statistical signature of many-body quantum interferenceNat. Photonics 12, 173-178 (2018).
  • C. Dittel, G. Dufour, M. Walschaers, G. Weihs, A. Buchleitner, and R. Keil, Totally destructive many-particle interferencePhys. Rev. Lett. 120, 240404 (2018).
  • C. Dittel, G. Dufour, M. Walschaers, G. Weihs, A. Buchleitner, and R. Keil, Totally destructive interference for permutation-symmetric many-particle statesPhys. Rev. A 97, 062116 (2018).
  • V. N. Shatokhin, M. Walschaers, F. Schlawin, and A. Buchleitner, Coherence turned on by incoherent lightNew J. Phys. 20, 113040 (2018).
  • M. Walschaers, S. Sarkar, V. Parigi, and N. Treps, Tailoring Non-Gaussian Continuous-Variable Graph StatesPhys. Rev. Lett. 121, 220501 (2018).
Research articles
Research articles
Review articles
Research articles
  • T. Zech, M. Walschaers, T. Scholak, R. Mulet, T. Wellens, and A. Buchleitner, Quantum transport in biological functional units: Noise, disorder, structureFluct. Noise Lett. 12, 1340007 (2013).
  • M. Walschaers, J. Fernandez-de-Cossio Diaz, R. Mulet, and A. Buchleitner, Optimally Designed Quantum Transport across Disordered NetworksPhys. Rev. Lett. 111, 180601 (2013).
  • M. Walschaers, R. Mulet, T. Wellens, and A. Buchleitner, Statistical theory of designed quantum transport across disordered networksPhys. Rev. E 91, 042137 (2015).