Speaker
Description
Research interest in indium antimonide (InSb) has increased in recent years thanks
to the possibility to overcome the limitation of its integration with lattice-mismatched materials in nano-heterostructures and consequent opportunities to realize novel quantum devices. Hence, precise control over morphology and crystalline quality becomes of paramount importance. Here, we show growth of InSb nanostructures on InAs and InP nanowire-stems without any pre-growth effort (patterning). InSb nanostructures such as nanowires (1D), nanoflags (2D), and nanocubes (3D) have been realized by means of Au-assisted chemical beam epitaxy by tailoring growth parameters like growth temperature, precursor fluxes, sample rotation, and substrate orientation[1]. Through morphological and crystallographic characterization, all the as-grown InSb nanoflags are found to be single-crystalline with zinc blende structure. The existence of two families of 2D nanostructures, characterized by an aperture angle at the base of 145◦ and 160◦, is observed and modelled. Furthermore, we have optimized the morphology of these free-standing 2D InSb nanoflags. In particular, using tapered nanowire-stems and precisely orienting the substrate with the help of reflection of high-energy electron diffraction patterns, we could maximize length and width and minimize the thickness of these nanoflakes[2]. The resulting flakes are large enough to precisely study their electrical characteristics. An electron mobility of ~29,500 cm2/Vs is measured at 4 K, which is the highest reported value for InSb flakes in literature[3-5]. This study provides useful guidelines for controlled growth of high-quality InSb nanostructures with different shape and envisions the use of 2D InSb flags for fabrication of novel quantum devices.
References
[1] I. Verma et al. Nanotechnology 2020, 31, 384002.
[2] I. Verma et al. Manuscript in preparation.
[3] D. Pan et al. Nano Lett. 2016, 16, 834.
[4] M. D. L. Mata et al. Nano Lett. 2016, 16, 825.
[5] S. Gazibegovic et al. Adv. Mater. 2019, 31, 1808181.
| Speaker Country | Italy |
|---|