Active orbital degree of freedom and potential spin-orbit-entangled moments in the Kitaev magnet candidate BaCo2(AsO4)2

• DOI: 10.1103/physrevb.106.195136
• Publication Date: 2022-11-18T15:02:15Z
• Authors: Subhasis Samanta; Panyalak Detratta...; Sutassana Na-Phat...; Heung-Sik Kim
• Keywords: Magnetism; Orbit (dynamics)

Candidate materials for the Kitaev spin liquid phase have been intensively studied recently because of their potential applications in fault-tolerant quantum computing. Although most studies on done $4d$- and $5d$-based transition-metal compounds, there has a growing research interest Co-based quasi-two-dimensional honeycomb magnets, such as ${\mathrm{BaCo}}_{2}{({\mathrm{AsO}}_{4})}_{2}$ formation spin-orbit-entangled ${J}_{\mathrm{eff}}=1/2$ pseudospin moments at ${\mathrm{Co}}^{2+}$ sites realizations Kitaev-like magnetism therein. Here, we obtain high-accuracy crystal electronic structure by employing combined density-functional dynamical mean-field theory calculations, which correctly capture Mott-insulating nature target system. We show that ions form high-spin configuration, $S=3/2$, with an active ${L}_{\mathrm{eff}}=1$ orbital degree freedom, absence spin-orbit coupling. The size trigonal distortion within ${\mathrm{CoO}}_{6}$ octahedra is found to be not strong enough completely quench so presence coupling can give rise exchange interaction. Our finding supports recent this compound other layered systems.