Heisenberg spin chain with random-sign couplings.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 39207732.
- Also identified by DOI 10.1073/pnas.2401292121 and PMC identifier 11388406.
- Licence recorded as CC BY-NC-ND.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
We study the 1D quantum Heisenberg chain with randomly ferromagnetic or antiferromagnetic couplings [a model previously studied by approximate strong-disorder renormalization group (RG)]. We find that, at least for sufficiently large spin <i>S</i>, the ground state has "spin glass" order. The spin waves on top of this state have the dynamical exponent [Formula: see text], intermediate between the values <i>z</i> = 1 of the antiferromagnet and <i>z</i> = 2 of the ferromagnet. Density matrix renormalization group (DMRG) simulations are in good agreement with the analytical results for spins <i>S</i> = 1 and [Formula: see text]. The case [Formula: see text] shows large finite size effects: We suggest that this case is also ordered, but with a small ordered moment.