Magnetic anisotropy energies and metal-insulator transitions in monolayers of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>α</mml:mi><mml:mtext>−</mml:mtext><mml:msub><mml:mi>RuCl</mml:mi><mml:mn>3</mml:mn></mml:msub></mml:mrow></mml:math> and <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> on graphene
Pedro H. Souza, Dominike Pacine de Andrade Deus, W. H. Brito, R. H. Miwa
Abstract
Transition metal (TM) trichlorides, with $4d$ or $5d$ electrons, are materials at the forefront of recent studies about the interplay of spin-orbit coupling (SOC) and strong Coulomb interactions. Within our first-principles calculations (DFT $+$ $U$ $+$ SOC) we study the effects of graphene on the electronic and magnetic properties of the monolayers (MLs) of $\ensuremath{\alpha}\text{\ensuremath{-}}{\mathrm{RuCl}}_{3}$ and ${\mathrm{OsCl}}_{3}$. Despite the spatially inhomogeneous $n$-type doping induced by graphene, we show that the occupancy of Ru-$4d$ $(\mathrm{Os}\text{\ensuremath{-}}5d)$ bands of MLs of $\ensuremath{\alpha}\text{\ensuremath{-}}{\mathrm{RuCl}}_{3}({\mathrm{OsCl}}_{3})$ can be tuned through external electric fields and allows the control of (i) metal-insulator transitions and (ii) the magnetic easy-axis and anisotropy energies. Our findings point toward the tuning of electronic and magnetic properties of TM trichloride MLs by using graphene and external electronic fields.