Synthesis of Superconductor-Topological Insulator Hybrid Nanoribbon Structures.

Superconductors in proximity to topological insulators (TIs) have the potential to unlock exotic quantum phenomena, such as Majorana fermions. Quasi-one-dimensional structures are particularly suited to host these quantum states. Despite the growth of TI nanostructures being relatively straightforward, the in situ synthesis of superconductor-TI structures has been challenging. Here, we present a systematic study of the growth of the s-wave superconductor Sn on the TI Bi₂Te₃ by physical vapor transport. If Sn does not enter the Bi₂Te₃ lattice as a dopant, two types of structures are formed: Sn nanoparticles, that cover Bi₂Te₃ plates and belts in a cloud-like shape, and thin Sn layers on Bi₂Te₃ plates, that appear in puddle-like recessions. These heterostructures have potential applications as novel quantum devices. The in-situ synthesis of superconductor-topological insulator (TI) heterostructures has been challenging. Here, for the first time, a study of the growth of the s-wave superconductor Sn on the TI Bi₂Te₃ by physical vapor transport was presented. Three different growth scenarios were observed: (1) Sn-decorated Bi₂Te₃, (2) local Sn-rich areas on Bi₂Te₃ plates, and (3) Sn-doped Bi₂Te₃. The different growth regimes are controlled by the Sn precursor quantity, carrier gas flux, and growth time. Each type has its specific application potentials. [ABSTRACT FROM AUTHOR]