6 papers
Pair binding and Hund's rule breaking in high-symmetry fullerenes
R. Rausch, C. Karrasch
Highly-symmetric molecules often exhibit degenerate tight-binding states at the Fermi edge. This typically results in a magnetic ground state if small interactions are introduced i…
Itinerant magnetism in the triangular lattice Hubbard model at half-doping: Application to twisted transition-metal dichalcogenides
Yuchi He, Roman Rausch, Matthias Peschke +4
We use unrestricted Hartree-Fock, density matrix renormalization group, and variational projected entangled pair state calculations to investigate the ground state phase diagram of…
Relaxation dynamics of a quantum spin coupled to a topological edge state
Qiyu Liu, Christoph Karrasch, Dante Marvin Kennes +1
A classical impurity spin coupled to the spinful Su-Schrieffer-Heeger (SSH) chain is known to exhibit complex switching dynamics with incomplete spin relaxation. Here, we study the…
Atacamite CuCl(OH) in High Magnetic Fields: Quantum Criticality and Dimensional Reduction of a Sawtooth-Chain Compound
L. Heinze, T. Kotte, R. Rausch +13
We report an extensive high-field study of atacamite CuCl(OH), a material realization of quantum sawtooth chains with weak interchain couplings, in continuous and pulsed ma…
Persistent Haldane Phase in Carbon Tetris Chains
Anas Abdelwahab, Christoph Karrasch, Roman Rausch
We introduce the concept of tetris chains, which are linear arrays of 4-site molecules that differ by their intermolecular hopping geometry. We investigate the fermionic symmetry-p…
Noncollinear phase of the antiferromagnetic sawtooth chain
R. Rausch, C. Karrasch
The antiferromagnetic sawtooth chain is a prototypical example of a frustrated spin system with vertex-sharing triangles, giving rise to complex quantum states. Depending on the in…