Computational exploration of a viable route to the Kitaev-quantum spin liquid phase in monolayer <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi>OsCl</mml:mi><mml:mn>3</mml:mn></mml:msub></mml:math>

In this computational study, we explore a viable route to access the Kitaev-quantum spin liquid (QSL) state in a recently synthesized monolayer of a so-called spin-orbit assisted Mott insulator <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"><a:msub><a:mi>OsCl</a:mi><a:mn>3</a:mn></a:msub></a:math>. In addition to other magnetic ground states in different regions, a substantial region of small <b:math xmlns:b="http://www.w3.org/1998/Math/MathML"><b:msub><b:mi>J</b:mi><b:mtext>H</b:mtext></b:msub></b:math>/<c:math xmlns:c="http://www.w3.org/1998/Math/MathML"><c:mi>U</c:mi></c:math> in our Hubbard <d:math xmlns:d="http://www.w3.org/1998/Math/MathML"><d:mi>U</d:mi></d:math>–Hund's <e:math xmlns:e="http://www.w3.org/1998/Math/MathML"><e:msub><e:mi>J</e:mi><e:mtext>H</e:mtext></e:msub></e:math> quantum phase diagram, obtained by combining second-order perturbation and pseudo-fermion functional renormalization group calculations, hosts Kitaev-QSL phase. Only the first neighbor Kitaev interaction of a smaller magnitude, nearly independent of the choice of <f:math xmlns:f="http://www.w3.org/1998/Math/MathML"><f:mi>U</f:mi></f:math>, is obtained in this region. Experimental tuning of the single parameter <g:math xmlns:g="http://www.w3.org/1998/Math/MathML"><g:msub><g:mi>J</g:mi><g:mtext>H</g:mtext></g:msub></g:math> to access the QSL state can purportedly be achieved with epitaxial strain in advanced crystal growth techniques. Furthermore, negligibly small farther neighbor interactions appear as a distinct feature of monolayer <h:math xmlns:h="http://www.w3.org/1998/Math/MathML"><h:msub><h:mi>OsCl</h:mi><h:mn>3</h:mn></h:msub></h:math>, suggesting this material to be a better candidate for the exploration of the possible Kitaev-QSL state than previously proposed materials. Published by the American Physical Society 2024