Large-Composition-Range Pure-Phase Homogeneous InAs1-xSbx Nanowires.

ABSTRACT

Narrow bandgap InAs1-xSbx nanowires show broad prospects for applications in wide spectrum infrared detectors, high-performance transistors, and quantum computation. Realizing such applications requires a fine control of the composition and crystal structure of nanowires. However, the fabrication of large-composition-range pure-phase homogeneous InAs1-xSbx nanowires remains a huge challenge. Here, we first report the growth of large-composition-range stemless InAs1-xSbx nanowires (0 ≤ x ≤ 0.63) on Si (111) substrates by molecular beam epitaxy. We find that pure-phase InAs1-xSbx nanowires can be successfully obtained by controlling the antimony content x, nanowire diameter, and nanowire growth direction. Detailed energy dispersive spectrum data show that the antimony is uniformly distributed along the axial and radial directions of InAs1-xSbx nanowires and no spontaneous core-shell nanostructures form in the nanowires. On the basis of field-effect measurements, we confirm that InAs1-xSbx nanowires exhibit good conductivity and their mobilities can reach 4200 cm2 V-1 s-1 at 7 K. Our work lays the foundation for the development of InAs1-xSbx nanowire optoelectronic, electronic, and quantum devices.