Large-Composition-Range Pure-Phase Homogeneous InAs 1- x Sb x Nanowires.

Narrow bandgap InAs 1- x Sb x 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 InAs 1- x Sb x nanowires remains a huge challenge. Here, we first report the growth of large-composition-range stemless InAs 1- x Sb x nanowires (0 ≤ x ≤ 0.63) on Si (111) substrates by molecular beam epitaxy. We find that pure-phase InAs 1- x Sb x 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 InAs 1- x Sb x nanowires and no spontaneous core-shell nanostructures form in the nanowires. On the basis of field-effect measurements, we confirm that InAs 1- x Sb x nanowires exhibit good conductivity and their mobilities can reach 4200 cm 2 V -1 s -1 at 7 K. Our work lays the foundation for the development of InAs 1- x Sb x nanowire optoelectronic, electronic, and quantum devices.