LABORATOIRE DE PHYSIQUE ET MODELISATION DES MILIEUX CONDENSES

Despite the large variety of phenomena and physical systems that we are interested in, our research is based on the use of a common set of theoretical and numerical tools. It aims at the development of fundamental understanding of classical and quantum phenomena in condensed matter physics as well as at applications to new sources of light, interferometry, high-precision measurements, quantum information and quantum technologies.

Research at LPMMC is structured in four main axes:

Brief descriptions of each axis are provided below.

Quantum physics

Quantum thermodynamics. This topic is at the intersection of quantum physics and non-equilibrium statistical physics, applied to mesoscopic systems. We study complex quantum systems coupled to simple reservoirs or simple quantum systems coupled to complex reservoirs using a “stochastic thermodynamics” formalism developed for open (markovian and non-markovian) quantum systems. Contact: Robert Whitney

Angular momentum of quantum vacuum. A new and completely unexplored subject is the understanding of the angular momentum of the quantum vacuum, when interacting with a rotating quantum object, possibly exposed to a time-dependent magnetic field. We aim at calculating and observing (in collaboration with colleagues at LNCMI) of classical and quantum Abraham forces arising in this context. Contact: Bart van Tiggelen

Quantum mechanics of anyons. Anyons are quasi-particles half-way between bosons and fermions. Our aim is to derive Hartree/Hartree-Fock-like models of anyons from many-body quantum mechanics, generalizing the mathematical methods available for bosons and fermions. Another research direction is the study of the fractional quantum Hall effect as a manifestation of anyon physics.

Quantum correlations in composite quantum systems. We develop a geometric approach to characterize and quantify entanglement and quantum discord in bipartite systems and apply this approach to study their time evolutions in specific models of condensed matter and quantum-optical systems, as well as in weak measurement processes. In particular, we want to understand geometrically why certain environments produce a fast decay of quantum correlations while others are much less detrimental and therefore more favorable for quantum technological applications.

Examples of recent publications:

Photon Hall Pinwheel Radiation of Angular Momentum by a Diffusing Magneto-Optical Medium, B. A. van Tiggelen and G. L. J. A. Rikken, Phys. Rev. Lett. 125, 133901 (2020)

Mixed-State Entanglement from Local Randomized Measurements, A. Elben, R. Kueng, H.-Y. Huang, R. van Bijnen, C. Kokail, M. Dalmonte, P. Calabrese, B. Kraus, J. Preskill, P. Zoller, and B. Vermersch, Phys. Rev. Lett. 125, 200501 (2020)

Statistical physics

Turbulence. We develop a theoretical approach to homogeneous and isotropic turbulence using the non-perturbative renormalisation group formalism. In collaboration with LEGI, we also study turbulence by direct numerical simulations of the Navier-Stokes equation. Contact: Leonie Canet, Vincent Rossetto

Imaging and radiative transfer. We work on the three-dimensional case of the radiative transfer by expanding the solution with respect to the scattering order and apply the results to imaging problems in optics, acoustics, and Earth sciences. We also study the role of longitudinal waves in the radiative transfer of electromagnetic waves. Contact: Vincent Rossetto

Excitons-polaritons. We pursue theoretical studies on exciton-polaritons by exploring new geometries, such as the honeycomb lattice. We also study the strongly interacting one-dimensional case and search for signatures of fermionization (Tonks-Girardeau regime) of polaritons. Contact: Anna Minguzzi

Information-theoretic approach to disordered systems. We work on developing an information-theoretic approach to the understanding of wave scattering in disordered media. The use of such concepts as the entropy and the information capacity is promoted instead of more traditional transport properties (transmittance, conductance, etc.). Contact: Sergey Skipetrov

Euclidean random matrix theory. Random matrices with elements defined via functions of positions in a Euclidean space are used to model the physics of waves in disordered media. We develop analytical approaches to study the statistical properties of eigenvalues and eigenvectors of such matrices and apply them to study wave propagation in disordered environments. Contact: Sergey Skipetrov

Examples of recent publications:

Analysis of the dissipative range of the energy spectrum in grid turbulence and in direct numerical simulations, A. Gorbunova, G. Balarac, M. Bourgoin, L. Canet, N. Mordant, and V. Rossetto, Phys. Rev. Fluids 5, 044604 (2020)