Low-temperature susceptibility upturn in the triangular spin tube

Determine whether the triangular spin-tube compound exhibits an upturn of the magnetic susceptibility at low temperatures.

Background

The paper examines a triangular spin tube composed of copper ions and compares thermal DMRG, exact diagonalization, finite-temperature Lanczos, and experimental results. For open tubes, the calculated susceptibility approaches the experimental data only slowly as the system size increases.

The existence of a low-temperature susceptibility upturn remains unresolved because the relevant low-temperature experimental measurements were not available. The numerical calculations alone do not establish whether the compound exhibits this behavior.

References

It remains open, whether the compound would show an upturn of the susceptibility at low temperatures since this was not measured at the time, unfortunately.

— Thermal DMRG for quasi one-dimensional magnetic molecules and chains  (2608.24608 - Horstmann et al., 25 Aug 2026) in Section 3.4, “Thermodynamics of a spin tube”