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/

Zendy Open

Presents the pdf analysis as premium feature

PDF Analysis

Insights

Presents the summarisation as premium feature

Summarisation

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the zaia usage as premium feature

ZAIA

Zendy Tools

Zendy Plus

Presents the access of premium content as premium feature

Premium Content

In this work we study theoretically the electronic properties of a sheet ofgraphene grown on a periodic heterostructure substrate. We write an effectiveDirac equation, which includes a dependence of both the band gap and the Fermivelocity on the position, due to the influence of the substrate. This way, bothbandgap and Fermi velocity enter the Dirac equation as operators. The Diracequation is solved exactly and we find the superlattice minibands with gaps dueto the breaking of translational symmetry induced by the underlyingheterostructure. The spatial dependence of the Fermi velocity makes the bandgap be indirect, bringing about interesting possibilities for applications inthe design of nanoelectronic devices. In the limit of constant Fermi velocitywe obtain a band structure, with direct band gap, very close to the onepreviously found in the literature, obtained using the transfer matrix method.

Indirect band gap in graphene from modulation of the Fermi velocity