8 papers
Composite Fields and Tree Expansions: A Unified Framework for Renormalized Vertex Decompositions
Oleksandr Sulyma, Benedikt Schneider
One-particle irreducible vertices encode renormalized interactions in quantum field theories, but their practical treatment remains challenging due to their high dimensionality and…
Finite-temperature spin diffusion in the two-dimensional XY model
Erik Fitzner, Byungjin Lee, Junhyeok Hur +4
We present a combined theory-experiment study to quantify spin diffusion in the square lattice quantum spin-1/2 XY model at finite temperature. On the theory side, we leverage a re…
Revisiting the - Heisenberg Model on a Triangular Lattice: Quasi-Degenerate Ground States and Phase Competition
Oleksandra Kovalska, Ester Pagès Fontanella, Benedikt Schneider +2
It is generally believed that the spin- triangular-lattice - Heisenberg model hosts a quantum spin liquid in the intermediate regime between the …
High-temperature series expansion of the dynamic Matsubara spin correlator
Ruben Burkard, Benedikt Schneider, Björn Sbierski
The high-temperature series expansion for quantum spin models is a well-established tool to compute thermodynamic quantities and equal-time spin correlations, in particular for fru…
Dynamic correlations of frustrated quantum spins from high-temperature expansion
Ruben Burkard, Benedikt Schneider, Björn Sbierski
For quantum spin systems in equilibrium, the dynamic structure factor (DSF) is among the most feature-packed experimental observables. However, from a theory perspective it is ofte…
Taming spin susceptibilities in frustrated quantum magnets: Mean-field form and approximate nature of the quantum-to-classical correspondence
Benedikt Schneider, Björn Sbierski
In frustrated magnetism, the empirically found quantum-to-classical correspondence (QCC) matches the real-space static susceptibility pattern of a quantum spin- model with its…