Effects of Facet Orientation on Relative Stability between Zinc Blende and Wurtzite Structures in Group III-V Nanowires

The relative stability between the wurtzite and zinc blende structures in InP, GaP, and GaAs nanowires with {111}/{1 (1) over bar 00} facets and those with {1 (1) over bar0}/{11 (2) over bar0} facets is systematically investigated using our empirical interatomic potential calculations in conjunction with first-principles calculations. Moreover, we discuss chemical trends in the structural stability of InP, GaP, and GaAs nanowires. Our calculations clarify that the wurtzite structure is stabilized over the entire diameter range for nanowires with {111}/{1 (1) over bar 00} facets. In contrast, for nanowires consisting of {1 (1) over bar0}/{11 (2) over bar0} facets, the crystal structure of nanowires depends on the nanowire diameter and the ionicity of semiconductors. This is because the surface energy difference between the {111} and {1 (1) over bar 00} surfaces is large compared with that between the {1 (1) over bar0} and {11 (2) over bar0} surfaces. The calculated results imply that the stability of nanowire side facets is an important factor determining the crystal structure. (C) 2010 The Japan Society of Applied Physics