Quantum matter
Topological Quantum Matter
David Carpentier, Pascal Degiovanni, Pierre Delplace, Andrei Fedorenko, Peter Holdsworth
We investigate how topological properties emerge in strongly interacting electrons in 2D materials. These effects arise from both microscopic multiband physics and large-scale semiclassical field couplings.
Using quantum Monte Carlo methods, we also study topological constraints in frustrated magnets in collaboration with experimental teams at CEA Saclay and CNRS Grenoble. Our work includes high-pressure studies of monopole crystallization and two-dimensional systems such as kagome lattices.
We analyze disorder and interaction effects in Dirac materials—focusing on boundaries, environmental coupling, and localization—and develop non-perturbative renormalization-group tools to map their phase diagrams.
We search for signatures of anyonic coherence in quantum Hall microwave resonators.
Spin–Phonon Probes of Magnetic Transitions
We study antiferromagnetic phase transitions through spin–phonon coupling measured with ultrasonic absorption. For spin-chain systems, we compute sound-velocity shifts and absorption using response theory and random-phase-approximation techniques to identify singular behavior near the Néel transition.
Advanced Numerical Methods
Fabio Mezzacapo, Tommaso Roscilde
We develop efficient numerical approaches for simulating quantum many-body systems in and out of equilibrium. Our methods rely on physically motivated, systematically improvable variational Ansätze with polynomial computational cost. By combining scale-invariant pair-product states with matrix-product and tensor-network structures—and potentially neural-network architectures—we aim to capture both short- and long-range entanglement effectively.