The Effect of Atomic Vacancies and Grain Boundaries on Mechanical Properties of GaN Nanowires
XIE Shi-Feng1, CHEN Shang-Da1**, SOH Ai-Kah2
1Faculty of Materials, Optoelectronics and Physics, Xiangtan University, Hunan 411105 2Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong
The Effect of Atomic Vacancies and Grain Boundaries on Mechanical Properties of GaN Nanowires
XIE Shi-Feng1, CHEN Shang-Da1**, SOH Ai-Kah2
1Faculty of Materials, Optoelectronics and Physics, Xiangtan University, Hunan 411105 2Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong
摘要Molecular dynamics simulations are carried out to investigate the influences of various defects on mechanical properties of wurtzite GaN nanowires by adopting the empirical Stillinger-Weber potential. Different types of vacancies and grain boundaries are considered and the uniaxial loading condition is implemented along the [001] direction. It is found that surface defects have less impact on Young's moduli and critical stresses of GaN nanowires compared with random defects. The grain boundary normal to the axial direction of a nanowire would not significantly affect Young's moduli of nanowires. However, the inversion domain grain boundaries with and without wrong bonds would significantly lower Young's moduli of GaN nanowires. In addition, the inversion domain grain boundary affects the critical stress of GaN nanowires more than the grain boundary with interface normal to the axial direction of the nanowire.
Abstract：Molecular dynamics simulations are carried out to investigate the influences of various defects on mechanical properties of wurtzite GaN nanowires by adopting the empirical Stillinger-Weber potential. Different types of vacancies and grain boundaries are considered and the uniaxial loading condition is implemented along the [001] direction. It is found that surface defects have less impact on Young's moduli and critical stresses of GaN nanowires compared with random defects. The grain boundary normal to the axial direction of a nanowire would not significantly affect Young's moduli of nanowires. However, the inversion domain grain boundaries with and without wrong bonds would significantly lower Young's moduli of GaN nanowires. In addition, the inversion domain grain boundary affects the critical stress of GaN nanowires more than the grain boundary with interface normal to the axial direction of the nanowire.
XIE Shi-Feng;CHEN Shang-Da**;SOH Ai-Kah
. The Effect of Atomic Vacancies and Grain Boundaries on Mechanical Properties of GaN Nanowires[J]. 中国物理快报, 2011, 28(6): 66201-066201.
XIE Shi-Feng, CHEN Shang-Da**, SOH Ai-Kah
. The Effect of Atomic Vacancies and Grain Boundaries on Mechanical Properties of GaN Nanowires. Chin. Phys. Lett., 2011, 28(6): 66201-066201.
[1] Johnson J C et al 2002 Nature Mater. 1 106
[2] Yan H Y, Xiu X Q et al 2010 Chin. Phys. Lett. 27 127801
[3] Stern E, Cheng G et al 2005 Nanotechnology 16 2941
[4] Chen Y, Jiang Y et al 2011 Chin. Phys. Lett. 28 048101
[5] Seryogin G, Shalish I et al 2005 Nanotechnology 16 2342
[6] Duan X F and Lieber C M 1999 J. Am. Chem. Soc. 122 188
[7] Kuykendall T, Pauzauskie P J, Zhang Y F, Goldberger J, Sirbuly D, Denlinger J and Yang P D 2004 Nature Mater. 3 524
[8] Liu B D, Bando Y, Tang C C, Xu F F and Golberg D 2005 Appl. Phys. Lett. 87 073106
[9] Kipshidze G, Yavich B et al 2005 Appl. Phys. Lett. 86 033104
[10] Feng G, Nix W D, Yoon Y K and Lee C J 2006 J. Appl. Phys. 99 074304
[11] Chen Y X, Stevenson I, Pouy R, Wang L D, McIlroy D N, Pounds T, Norton M G and Aston D E 2007 Nanotechnology 18 135708
[12] Wang Z G, Zu X T, Yang L, Gao F and Weber W J 2007 Phys. Rev. B 76 045310
[13] Wang Z G, Zu X T, Yang L, Gao F and Weber W J 2008 Physica E 40 561
[14] Moon W H, Kim H J and Choi C H 2007 Scr. Mater. 56 345
[15] Agrawal R, Peng B and Espinosa H D 2009 Nano Lett. 9 4177
[16] http://lammps.sandia.gov/
[17] Béré A, Chen J, Ruterana P, Serra A and Nouet G 2002 Compd. Mater. Sci. 24 144
[18] Hoover W G 1985 Phys. Rev. A 31 1695
[19] Rafii-Tabar H 2004 Phys. Rep. 390 235
Rafii-Tabar H 2004 Phys. Rep. 394 357 (Erratum)
[20] Nam C Y, Jaroenapibal P, Tham D, Luzzi D E, Evoy S and Fischer J E 2006 Nano Lett. 6 153
[21] Tham D, Nam C Y and Fischer J E 2006 Adv. Funct. Mater. 16 1197
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