English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Density functional theory calculations are used to systematically investigatethe structural and electronic properties of MX$_2$ transition metaldichalcogenide monolayers with M = Cr, Mo, W and X = S, Se, Te that are dopedwith single (V, Nb, Ta) and double (Ti, Zr, Hf) acceptor dopants on the M sitewith local $D_{3h}$ symmetry in the dilute limit. Three impurity levels thatarise from intervalley scattering are found above the valence band maxima(VBM): an orbitally doubly degenerate $e'$ level bound to the $K/K'$ VBM and asingly degenerate $a'_1$ level bound to the $\Gamma$-point VBM. Replacing Swith Se or Te lowers the $\Gamma$ point VBM substantially with respect to the$K/K'$ VBM bringing the $a'_1$ level down with it. The relative positions ofthe impurity levels that determine the different structural and electronicproperties of the impurities in $p$-doped MX$_2$ monolayers can thus be tunedby replacing S with Se or Te.  Single acceptors introduce a magnetic moment of 1$\, \mu_{\rm B}$ in allMX$_2$ monolayers. Out-of-plane magnetic anisotropy energies as large as 10meV/dopant atom are found thereby satisfying an essential condition forlong-range ferromagnetic ordering in two dimensions. For double acceptors inMS$_2$ monolayers, both holes occupy the high-lying $a'_1$ level with oppositespins so there is no magnetic moment; in MSe$_2$ and MTe$_2$ monolayers theholes occupy the $e'$ level, a Jahn-Teller (JT) distortion wins the competitionwith exchange splitting resulting in the quenching of the magnetic moments.Even when the JT distortion is disallowed, magnetic double acceptors have alarge in-plane magnetic anisotropy energy that is incompatible with long-rangemagnetic ordering in two dimensions. ....

A DFT study of the structural and electronic properties of single and double acceptor dopants in MX2 monolayers