NPOL > Members > [Seminar] 2013, MSE Special Seminar, Prof. Young Joon Hong

[Seminar] 2013, MSE Special Seminar, Prof. Young Joon Hong
[Seminar] 2013, MSE Special Seminar, Prof. Young Joon Hong
글쓴이 : 최고관리자   날짜 : 13-07-10 21:47  
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MSE special seminar - Prof. Young Joon Hong (Sejong University)

Title: Van der Waals epitaxial double heterostructures: InAs/single-layer graphene/InAs



Abstract
Epitaxial InAs/graphene/InAs double heterostructures were fabricated using vapor-phase transport-based van der Waals (vdW) epitaxy of InAs on suspended single-layer graphene (S-SLG). InAs nanostructures of high density were grown on both sides of S-SLG using metal–organic vapor-phase epitaxy, to produce epitaxial InAs/SLG/InAs double heterostructures with high yield. Importantly, InAs nanostructures favorably formed along the zinc-blende [111]B direction, normal to the SLG surface, resulting in graphene-sandwiched double heterostructures with polarity inversion. Crystallographic analyses were performed by atomic resolution transmission electron microscopy with elemental mapping. The electronic structure and binding energy of vdW epitaxial InAs/S-SLG structures, determined from density functional computations, explain why the [111]B-oriented InAs nanostructures diametrically formed at the same position on both sides of the S-SLG by vdW epitaxy. Our work provides a new important methodology and principles of fabricating the graphene-based epitaxial multiple heterostructures for new functional device applications.