6 papers
Probing Bardeen-Cooper-Schrieffer pairing and quasiparticle formation in ultracold gases by Rydberg atom spectroscopy
Emilio Ramos RodrÃguez, Marcel Gievers, Richard Schmidt
Locally probing pairing in fermionic superfluids, ranging from micro- to macroscopic scales, has been a long-standing challenge. Here, we investigate a new approach that uses Rydbe…
Stabilizing the parquet problem
Herbert EÃl, Stefan Rohshap, Marcel Gievers +3
We systematically analyze the stability of the iterative solution of the parquet equations by studying the spectrum of the Jacobian associated with the commonly used damped fixed-p…
Functional renormalization with interaction flows: A single-boson exchange perspective and application to electron-phonon systems
Aiman Al-Eryani, Marcel Gievers, Kilian Fraboulet
The functional renormalization group (fRG) is acknowledged as a powerful tool in quantum many-body physics and beyond. On the technical side, conventional implementations of the fR…
Single-boson exchange formulation of the Schwinger-Dyson equation and its application to the functional renormalization group
Miriam Patricolo, Marcel Gievers, Kilian Fraboulet +6
We extend the recently introduced single-boson exchange formulation to the computation of the self-energy from the Schwinger--Dyson equation (SDE). In particular, we derive its exp…
Subleading logarithmic behavior in the parquet formalism
Marcel Gievers, Richard Schmidt, Jan von Delft +1
The Fermi-edge singularity in x-ray absorption spectra of metals is a paradigmatic case of a logarithmically divergent perturbation series. Prior work has thoroughly analyzed the l…
Quantum wires with local particle loss: Transport manifestations of fluctuation-induced effects
Marcel Gievers, Thomas Müller, Heinrich Fröml +2
We investigate the transport properties of a quantum wire of weakly interacting fermions in the presence of local particle loss. We calculate current and conductance in this system…