AI Article Synopsis
- Lattice-matched graphene on hexagonal boron nitride can potentially create a band gap, but achieving this has been challenging due to material strain.
- Researchers successfully grew aligned, lattice-matched graphene using high temperatures (1600-1710 °C) alongside a unique moiré pattern with significant strain variations.
- The study found that the graphene's conductance is lower compared to other defect types, linking these findings to theoretical models predicting band gap development in graphene/boron nitride structures.
Article Abstract
Lattice-matched graphene on hexagonal boron nitride is expected to lead to the formation of a band gap but requires the formation of highly strained material and has not hitherto been realized. We demonstrate that aligned, lattice-matched graphene can be grown by molecular beam epitaxy using substrate temperatures in the range 1600-1710 °C and coexists with a topologically modified moiré pattern with regions of strained graphene which have giant moiré periods up to ∼80 nm. Raman spectra reveal narrow red-shifted peaks due to isotropic strain, while the giant moiré patterns result in complex splitting of Raman peaks due to strain variations across the moiré unit cell. The lattice-matched graphene has a lower conductance than both the Frenkel-Kontorova-type domain walls and also the topological defects where they terminate. We relate these results to theoretical models of band gap formation in graphene/boron nitride heterostructures.
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| http://dx.doi.org/10.1021/acs.nanolett.7b04453 | DOI Listing |
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