4 papers
To infinity and back -- graph expansions of light-matter systems
Andreas Schellenberger, Kai P. Schmidt
We present a method for performing a full graph expansion for light-matter systems, utilizing the linked-cluster theorem. This method enables us to explore corrections to the…
Quantitative approach for the Dicke-Ising chain with an effective self-consistent matter Hamiltonian
J. Leibig, M. Hörmann, A. Langheld +2
In the thermodynamic limit, the Dicke-Ising chain maps exactly onto an effective self-consistent matter Hamiltonian with the photon field acting solely as a self-consistent effecti…
Comment on "Role of Matter Interactions in Superradiant Phenomena"
Max Hörmann, Anja Langheld, Jonas Leibig +2
Recently, Mendonça et al. [arXiv:2503.04961] investigated the Dicke-XXZ model and the Dicke-Ising model. For the latter model, their calculated quantum phase diagram contradicts cl…
Quantum criticality and excitations of a long-range anisotropic -chain in a transverse field
P. Adelhardt, J. A. Koziol, A. Schellenberger +1
The critical breakdown of a one-dimensional quantum magnet with long-range interactions is studied by investigating the high-field polarized phase of the anisotropic XY model in a…