Comparative study of adsorption characteristics of Cs on the GaN （0001） and GaN （0001） surfaces
The adsorption characteristics of Cs on GaN （0001） and GaN （0001） surfaces with a coverage from 1/4 to 1 monolayer have been investigated using the density functional theory with a plane-wave uttrasoft pseudopotential method based on first-principles calculations. The results show that the most stab...
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| Published in | 中国物理B：英文版 Vol. 21; no. 6; pp. 437 - 442 |
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| Main Author | |
| Format | Journal Article |
| Language | English |
| Published |
2012
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| Subjects | |
| Online Access | Get full text |
| ISSN | 1674-1056 2058-3834 |
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| Summary: | The adsorption characteristics of Cs on GaN （0001） and GaN （0001） surfaces with a coverage from 1/4 to 1 monolayer have been investigated using the density functional theory with a plane-wave uttrasoft pseudopotential method based on first-principles calculations. The results show that the most stable position of the Cs adatom on the GaN （0001） surface is at the N-bridge site for 1/4 monolayer coverage. As the coverage of Cs atoms at the N-bridge site is increased, the adsorption energy reduces. As the Cs atoms achieve saturation, the adsorption is no longer stable when the coverage is 3/4 monolayer. The work function achieves its minimum value when the Cs adatom coverage is 2/4 monolayer, and then rises with Cs atomic coverage. The most stable position of Cs adatoms on the GaN （000i） surface is at H3 site for 1/4 monolayer coverage. As the Cs atomic coverage at H3 site is increased, the adsorption energy reduces, and the adsorption is still stable when the Cs adatom coverage is 1 monolayer. The work function reduces persistently, and does not rise with the increase of Cs coverage. |
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| Bibliography: | GaN surface, electronic structure, adsorption energy, work function 11-5639/O4 The adsorption characteristics of Cs on GaN （0001） and GaN （0001） surfaces with a coverage from 1/4 to 1 monolayer have been investigated using the density functional theory with a plane-wave uttrasoft pseudopotential method based on first-principles calculations. The results show that the most stable position of the Cs adatom on the GaN （0001） surface is at the N-bridge site for 1/4 monolayer coverage. As the coverage of Cs atoms at the N-bridge site is increased, the adsorption energy reduces. As the Cs atoms achieve saturation, the adsorption is no longer stable when the coverage is 3/4 monolayer. The work function achieves its minimum value when the Cs adatom coverage is 2/4 monolayer, and then rises with Cs atomic coverage. The most stable position of Cs adatoms on the GaN （000i） surface is at H3 site for 1/4 monolayer coverage. As the Cs atomic coverage at H3 site is increased, the adsorption energy reduces, and the adsorption is still stable when the Cs adatom coverage is 1 monolayer. The work function reduces persistently, and does not rise with the increase of Cs coverage. Du Yu-Jie, Chang Ben-Kang, Wang Hong-Gang, Zhang Jun-Ju, and Wang Mei-Shan（a） Department of Physics and Electronic Sciences, fnstitute of Bingzhou, Bingzhou 256603, China b） Institute of Electronic Engineering and Opto-Electric Technology, Nanjing University of Science and Technology, Nanjing 210094, China c） School of Physics and Optoelectronic Engineering, Ludong University, Yantai 264025, China |
| ISSN: | 1674-1056 2058-3834 |