Computational exploration of a viable route to Kitaev-quantum spin liquid phase in OsCl$_3$

Abstract

In this computational study, we explore a viable route to access the Kitaev-Quantum Spin Liquid (QSL) state in recently synthesized monolayer of a so-called spin-orbit assisted Mott insulator OsCl$_3$. In addition to other magnetic ground states in different regions, the small $J_\text{H}$/$U$ region of our Hubbard $U$--Hund's $J_\text{H}$ quantum phase diagram, obtained by combining second-order perturbation and pseudo-Fermion renormalization group calculations, hosts Kitaev-QSL phase. Only Kitaev interaction of a smaller magnitude is obtained in this region. Negligibly small farther neighbor interactions appear as a distinct feature of monolayer \os, suggesting this material to be a better candidate for the exploration of possible Kitaev-QSL state than earlier proposed materials. Insights from our study might be useful to probe magnetic phase transitions by purportedly manipulating $U$ and $J_\text{H}$ with epitaxial strain in advanced crystal growth techniques.