کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1552507 1513204 2016 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
The electronic properties of bare and alkali metal adsorbed two-dimensional GeSi alloy sheet
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد مواد الکترونیکی، نوری و مغناطیسی
پیش نمایش صفحه اول مقاله
The electronic properties of bare and alkali metal adsorbed two-dimensional GeSi alloy sheet
چکیده انگلیسی
In this paper, the structural and electronic properties of both bare and alkali metal (AM) atoms adsorbed two-dimensional GeSi alloy sheet (GeSiAS) are investigated by means of first-principles calculations. The band gaps of bare GeSiAS are shown slightly opened at Dirac point with the energy dispersion remain linear due to the spin-orbit coupling effect at all concentrations of Ge atoms. For metal adsorption, AM atoms (including Li, Na and K) prefer to occupy the hexagonal hollow site of GeSiAS and the primary chemical bond between AM adatom and GeSiAS is ionic. The adsorption energy has an increase tendency with the increase of the Ge concentration in supercell. Besides, single-side adsorption of AM atoms introduces band gap at Dirac point, which can be tuned by the Ge concentration and the species of AM atoms. The strong relation between the band gaps and the distribution of Si and Ge atoms inside GeSiAS are also demonstrated. The opened band gaps of AM covered GeSiAS range from 14.8 to 269.1 meV along with the effective masses of electrons ranging from 0.013 to 0.109 me, indicating the high tunability of band gap as well as high mobility of carriers. These results provide a development in two-dimensional alloys and show potential applications in novel micro/nano-electronic devices.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Superlattices and Microstructures - Volume 97, September 2016, Pages 250-257
نویسندگان
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