Determine the electronic filling factor of CeCo₂Ga₈

Determine the appropriate conduction-electron filling factor n for CeCo₂Ga₈ in the one-dimensional Kondo-Heisenberg model, so that the model parameters and corresponding spectral features can be quantitatively assigned.

Background

The DMRG calculations require the hopping amplitude, conduction-electron filling n, Kondo exchange J_K, and Heisenberg exchange J_H as input parameters. Although the hopping and an estimate of J_H are available for CeCo₂Ga₈, the experimentally appropriate filling factor is not established. The authors therefore use n = 0.83 for comparison with earlier theoretical work and additionally explore n = 0.67, but they do not identify the physical value for the material.

Resolving the filling factor is necessary for determining realistic model parameters and for making a quantitative rather than merely qualitative comparison between the calculated dynamical spin structure factor and the neutron-scattering spectrum.

References

Secondly, the appropriate filling factor $n$ for CeCo$_2$Ga$_8$ is unknown; we used $n=0.83$ in Fig. \ref{fig:DMRG} to compare with previous theoretical studies.

— Incommensurate spin fluctuations in one-dimensional Kondo metal CeCo2Ga8  (2608.26071 - Huang et al., 26 Aug 2026) in Section DMRG simulations, paragraph beginning “Helpful though they are”