activity
20242026
collaborators

7 papers

cond-mat.str-el2026

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…

cond-mat.str-el2025

Quantum decay of magnons in the unfrustrated honeycomb Heisenberg model

Calvin Krämer, Dag-Björn Hering, Vanessa Sulaiman +3

We investigate the physical properties of elementary magnon excitations of the ordered antiferromagnetic Heisenberg model on the honeycomb lattice using quantum Monte Carlo (QMC) s…

cond-mat.str-el2025

Immobile and mobile excitations of three-spin interactions on the diamond chain

M. Bayer, M. Vieweg, K. P. Schmidt

We present a solvable one-dimensional spin-1/2 model on the diamond chain featuring three-spin interactions, which displays both, mobile excitations driving a second-order phase tr…

quant-ph2025

Quantum algorithm for one-quasiparticle excitations in the thermodynamic limit via cluster-additive block diagonalization

Sumeet, M. Hörmann, K. P. Schmidt

We propose a quantum algorithm for computing one-quasiparticle excitation energies in the thermodynamic limit by combining numerical linked-cluster expansions (NLCEs) and the varia…

cond-mat.str-el2025

Quantum Monte Carlo study of the bond- and site-diluted transverse-field Ising model

C. Krämer, M. Hörmann, K. P. Schmidt

We study the transverse-field Ising model on a square lattice with bond- and site-dilution at zero temperature by stochastic series expansion quantum Monte Carlo simulations. Tunin…

cond-mat.str-el2024

Quantum melting of long-range ordered quantum antiferromagnets investigated by momentum-space continuous similarity transformations

Dag-Björn Hering, Matthias R. Walther, Kai P. Schmidt +1

We apply continuous similarity transformations (CSTs) to study the zero-temperature breakdown of long-range ordered quantum antiferromagnets. The CST flow equations are truncated i…