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"Lapisan tunggal atom silikon dan karbon dalam dua dimensi dengan kisi berbentuk heksagonal telah dikenal dengan nama silicene dan graphene. Selain atom penyusunnya, sedikit perbedaan tambahan antara keduanya adalah bahwa silicene memiliki ketebalan yang lebih besar daripada graphene karena kisi heksagonnya tertekuk. Dengan mengganti semua atom silikon-28 (atau karbon-12) pada silicene (atau graphene) dengan isotop stabilnya, yaitu silikon-29 dan silikon-30 (atau karbon-13), memungkinkan untuk terjadinya rekayasa struktur pita pada material tersebut yang menjadikannya sebuah material isotopic homojunction, yang artinya sebuah heterostructure dapat dibuat dengan mengganti atom-atom pada sel satuan dengan isotopnya. Pada studi ini, kami menginvestigasi efek dari isotop silikon dan karbon terhadap struktur pita silicene dan graphene dengan menggunakan first-principles calculations. Kami berhipotesis bahwa akan ada perubahan pada konstanta kisi silicene maupun graphene karena substitusi isotop yang akan diakomodasi di dalam interaksi elektron-fonon yang menyebabkan energi dispersi elektron dapat termodifikasi pada orde meV. Untuk dispersi fonon, massa isotop akan memberikan kon-tribusi dominan terhadap pergeseran frekuensi fonon.

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Single layers of silicon and carbon atoms in two dimensions with a hexagonal/honeycomb lattice are well known as silicene and graphene. Apart from the constituent atoms, an additional difference between the two is that silicene has a slightly larger thickness than graphene because its hexagon lattice is bent forming the so-called buckled hexagonal lattice. By replacing all the silicon-28 (or carbon-12) atoms in silicene (or graphene) with their stable isotopes, i.e. silicon-29 andsilicon-30 (or carbon-13), it is possible to engineer the band structure of the materialthat transforms it into an isotopic homojunction, which means that a heterostructure can be created by replacing the atoms in the unit cell with their isotopes. In this study, we investigate the effect of silicon and carbon isotopes on the band structure of silicene and graphene using first-principles calculations. We hypothesize that there will be a change in the lattice constants of both silicene and graphenedue to the substitution of the isotopes that will be accommodated in the electron-phonon interactions that cause the electron dispersion energy to be modified on the order of meV. For phonon dispersion, the mass of the isotope will make a dominant contribution to the shift in phonon frequency."

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