Thermal density matrix renormalization group for highly frustrated quantum spin chains: A user perspective

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

卷:487

Article

Heveling, Robin¹  Richter, Johannes^2,3  Schnack, Juergen⁴ 

[1] Osnabruck Univ, Dept Phys, Barbarastr 7, D-49076 Osnabruck, Germany

[2] Magdeburg Univ, Inst Theoret Phys, POB 4120, D-39016 Magdeburg, Germany

[3] Max Planck Inst Phys Komplexer Syst, Nothnitzer Str 38, D-01187 Dresden, Germany

[4] Bielefeld Univ, Dept Phys, POB 100131, D-33501 Bielefeld, Germany

关键词: Molecular magnetism;    Approximate methods;    Numerical simulation studies;    DMRG;   

DOI  :  10.1016/j.jmmm.2019.165327

来源: Elsevier

【 摘 要 】

The thermal density matrix renormalization group (DMRG) is investigated with emphasis on employability in molecular magnetism studies. To this end magnetic observables at finite temperature are evaluated for two one-dimensional quantum spin systems: a Heisenberg chain with nearest-neighbor antiferromagnetic interaction and a frustrated sawtooth (delta) chain. It is found that thermal DMRG indeed accurately approximates magnetic observables for the chain as well as for the sawtooth chain, but in the latter case only for sufficiently high temperatures. We speculate that the reason is due to the peculiar structure of the low-energy spectrum of the sawtooth chain induced by frustration.

【 授权许可】

Free