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arXiv · 2212.14793

Deformation Effect on Graphene Quantum Dot/Graphane and Silicene Quantum Dot/Silicane array

Bi-Ru Wu
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Abstract

This article presents a design for the two-dimensional heterostructure (2DH) systems of graphane quantum dot array in graphane (GQD/Graphane), and silicene quantum dot array in silicane (SiQD/Silicane). A first-principles method was used to evaluate the deformation effect for magnetism as well as the electronic properties for the 2DH systems. The energy levels of quantum dot (QD) array and the band structure of its hydrogenated counterpart are coupling for both 2DH systems of C and Si. The hydrogenated part shares part of strain on QD array, however, the strain sharing effect is stronger in SiQD/silicane than in GQD/graphane. The strain sharing enhances the band coupling of the QD and its hydrogen counterpart in the low energy region. The band coupling alters the electronic properties of the 2DH systems and change the magnetic properties of triangular and parallelogram of SiQD/Silicane array under compressive strain larger than 5%. Strain modulates the band gap of the 2DH system. For SiQD/Silicane systems, the homogeneous strain not only induces the phase transition of from semiconductor to metal, but also remove the magnetism of triangular and parallelogram SiQD array. The 2DH system can be used in the design of nanoelectronic devices and binary logic based on nanoscale magnetism.

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Bi-Ru Wu. 2022-12-30. Deformation Effect on Graphene Quantum Dot/Graphane and Silicene Quantum Dot/Silicane array. https://arxiv.org/abs/2212.14793

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