The Case of Itinerant Magnetism in CaMn$_{2}$Al$_{10}$: Self-Consistent Renormalisation (SCR) Theory Study

TL;DR

This study applies self-consistent renormalization theory to CaMn$_{2}$Al$_{10}$, confirming its itinerant magnetic nature through theoretical calculations that match experimental susceptibility data and revealing strong Mn-Al hybridization.

Contribution

The paper provides a quantitative analysis of itinerant magnetism in CaMn$_{2}$Al$_{10}$ using SCR theory, supported by DFT calculations, which is novel for this compound.

Findings

Good agreement between calculated and experimental susceptibility data

Estimated electronic correlation strength ($I=0.3136$ eV)

Confirmed strong Mn-Al hybridization as key to itinerant magnetism

Abstract

We have applied the powerful self-consistent renormalization theory of spin fluctuations for the system CaMn$_{2}$Al$_{10}$ discovered in 2015 and was conjectured to be an itinerant magnet. We have calculated the inverse static (paramagnetic) susceptibility and have compared it with the experimental data (Phys. Rev. B 92, 020413, 2015). The agreement is very good. We have calculated spin fluctuations at various temperatures and have also estimated the strength of the electronic correlation i.e., ($I=0.3136$ eV) in the Hubbard Hamiltonian. Based on our quantitative explanation of the inverse static (paramagnetic) susceptibility data within the framework of SCR theory, we can decisively conclude CaMn$_{2}$Al$_{10}$ exhibits the phenomena of itinerant magnetism. Further, our DFT and DFT+U calculations corroborate the strong Mn-Al hybridization which is the key behind the itinerant magnetism in this system. Our estimated correlations strength will provide a foundation for further studies of itinerant magnetism in this system.